The document provides a comprehensive overview of drugs used in obstetrics, detailing their classifications and specific applications, including commonly used medications like folic acid, iron, and antihypertensive drugs such as methyldopa and labetalol. It highlights the importance of these drugs in managing maternal and fetal health, including risks associated with their use during different trimesters of pregnancy. Additionally, it discusses pharmacokinetics, dosages, contraindications, and adverse effects for various drugs, emphasizing the need for careful monitoring and nursing considerations.

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TO GET FURTHER MORE NOTES:
https://sharmanotes.blogspot.com/
Prasad Sharma VG
Ganga Prasad V
M.Sc (N) in Child Health Nursing

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INDEX
Sl. No Drugs Name Page No.
01  Introduction
 Classification of Obstetrical drugs
4
4-5
02 Commonly using Drugs in Obstetrics
 Folic Acid
 Iron
 Calcium citrate
6
6-7
8-10
10-11
03 Anti-Hypertensive Drugs
 Methyldopa
 Labetalol
 Nifedipine
 Hydralazine
 Propranolol (Inderal)
 Prazosin
 Nitroglycerin
 Sodium Nitroprusside
 Captopril
12
12-14
14-16
16-17
18-19
20-21
21-23
23-24
24-25
25-26
04 Diuretics
 Furosemide
26
27-28
05 Tocolytic Agents
 Betamimetic
 Indomethacin
 Magnesium Sulfate
 Oxytocin receptor antagonists
28
29-30
30-32
32-34
34-36
06 Oxytocics
 Oxytocin
 Ergot derivatives
36-44
44-46

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 Prostaglandins 46-48
07 Anticonvulsants
 Magnesium sulfate
 Diazepam (Valium)
 Phenytoin
 Phenobarbitone (Luminal)
49-51
51-53
53-54
54-56
08 Anticoagulants
 Heparin
 Warfarin Sodium
56-57
58-60
09 Analgesics
 Valethemate bromide (Epidosin)
 Tramadol
 Pethidine
 Fentanyl
 Promethazine
60-61
61-62
62-64
64-65
66-67
10 Coagulant
 Vitamin K 67-68
11 Teratogenic Drugs 69-73
12 Emergency drugs in Neonates 74-75
13 Reference 76

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INTRODUCTION
Drugs used in obstetrics have a huge impact on the outcome of both mother and baby.
Drugs used during first trimester can produce congenital malformation and the period of greatest
risk is from the third to eleven weeks of pregnancy. During second and third trimester drugs can
affect the growth and functional development of the fetus or they can have toxic effect on fetus
tissues.
CLASSIFICATION OF DRUGS USED IN PREGNANCY:
 Commonly used drugs:
 Folic Acid
 Iron
 Calcium
 Anti-hypertensive drugs:
 Methyldopa
 Labetalol
 Propranolol (Inderal)
 Hydralazine
 Nifedipine
 Tocolytic Agents:
 Betamimetics:
 Isoxuprine Hydrochloride
 Ritrodrine Hydrochloride
 Terbutaline
 Diazoxide
 Sodium Nitroprusside
 Prazosin
 Nitroglycerine
 Captopril
DRUGS USED IN OBSTETRICS
 Diuretics:
 Furosemide (Lasix)
 Hydrochlorothiazide
 Spironolactone (Aldactone)

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 Indomethacin
 Calcium channel Blockers
 Nifidepine
 Megnesium sulphate
 Oxytocin antagonists
 Atosiban
 Nitric Oxide (NO) Donors:
 Anticoagulants:
 Heparin Sodium
 Warfarin Sodium (Cumadin)
 Analgesics:
 Pethidine (Mereridine)
 Fenetanyl
 Promethazine (Phenergan)
 Anticonvulsant drugs:
 Magnesium Sulfate
 Diazepam
 Phenytoin (Dilantin)
 Phenobarbitone (Luminal)
 Teratogenic Drugs
 Emergency drugs used in Neonates
 Oxytocics
 Oxytocin
 Ergot derivatives
 Prostaglandins

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COMMONLY USED DRUGS
FOLIC ACID
Taking a prenatal vitamin with the recommended 400 micrograms (mcg) of folic acid before and
during pregnancy can help prevent birth defects of baby's brain and spinal cord.
Mechanism of Action:
 Necessary for formation of coenzymes in metabolic systems (purine and pyrimidine
synthesis required for maintenance in erythropoiesis);
 Stimulates platelet production in folate deficiency anemia.
 Enhances elimination of formic acid in methanol toxicity via provision of coenzyme to
folate dehydrogenase.
Indications
1. Megaloblastic or Macrocytic anemia during pregnancy to prevent fetal damage.
2. Prevent fetal neural tube defect during pregnancy.
Contraindications:
 Untreated vitamin B12 deficiency.
Dose and Route:
Tablet:
 400mcg, 800mcg, 1mg: OD orally
Injectable solution:
 5mg/ml: IM Or subcutaneously daily
Adverse effects
 Bronchospasm
 Erythema
 Malaise
 Pruritus
 Rash

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Pharmacokinetics:
 Metabolism: Metabolized in the liver to N-methyltetrahydrofolic acid, the main form
of folate storage and transport.
 Excretion: A single 0.1-0.2 mg dose usually results in only a trace amount of drug in
urine.
 After administering large doses, excessive folate is excreted unchanged in urine.
Nursing consideration
Assessment
 History: Allergy to folic acid preparations, pernicious, aplastic, normocytic anemias;
lactation.
 Physical: Skin lesions, color; R, adventitious sounds; CBC, Hgb, Hct, serum folate levels,
serum vitamin B12 levels, and Schilling test.
Interventions
 Administer orally if at all possible. With severe GI malabsorption or very severe disease,
give IM or subcutaneously.
 Test using Schilling test and serum vitamin B12 levels to rule out pernicious anemia.
Therapy may mask signs of pernicious anemia while the neurologic deterioration
continues.
 Monitor patient for hypersensitivity reactions, especially if drug previously taken.
 Keep supportive equipment and emergency drugs readily available in case of serious
allergic response.
 Patient with H/O fetal neural tube defect in pregnancy should increase folic acid intake 1
month before and 3 months after conception.

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IRON (Ferrous Fumarate)
This higher hemoglobin concentration as a result of an improved iron supply not only increases
the oxygen-carrying capacity, but it also provides a buffer against the blood loss that will occur
during delivery.
Mechanism of Action
Iron is necessary for the production of hemoglobin. Iron-deficiency can lead to decreased
production of hemoglobin and a microcytic, hypochromic anemia.
Indications
 Iron deficiency
 As a supplement during pregnancy
Contraindications
 Primary haemolytic anemia
 Peptic ulcer disease
 Ulcerative colitis
 Repeated blood transfusions
Dosage:
 Iron Deficiency anaemia: 100 to 200 mg elemental iron per day. This equates to Fersamal
1 tablet BD/TID times a day.
 Prophylaxis: Ferrous sulphate 200 mg OD/BD. 60 to 120 mg elemental iron per day. This
equates to Fersamal 1 tablet once or twice daily.
Available forms
 Available without a prescription. Ferrous fumarate is 30% elemental iron.
 Capsules (extended-release): 325 mg

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 Drops: 45 mg/0.6 ml
 Suspension: 100 mg/5 ml
 Tablets: 63 mg, 195 mg, 200 mg, 324 mg, 325 mg, 350 mg
 Tablets (chewable): 100 mg
Side Effects:
 Diarrhea.
 Constipation.
 Change in color of stool to green.
 Stomach cramps.
Pharmacokinetics:
 Absorption: Absorbed from the entire length of the GI tract, but primary absorption sites
are the duodenum and proximal jejunum. food may decrease absorption by 40% to 60%.
 Distribution: Transported through GI mucosal cells directly into the blood, where it’s
immediately bound to a carrier protein, transferrin, and transported to the bone marrow
for incorporation into hemoglobin. Iron is highly protein-bound.
 Storage: These stores are a reserve of iron for synthesis of haemoglobin, myoglobin, and
iron containing enzymes.
 Excretion: The loss usually occurs in nails, hair, feces, and urine; trace amounts are lost
in bile and sweat.
Management:
Administration advice:
 Coffee, tea, milk, cereal, dietary fiber, and phosphate containing carbonated drinks
decrease iron absorption.
 Supplements containing calcium, zinc, manganese, or copper decrease iron absorption.

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 Antacids, H2 blockers, and proton pump inhibitors decrease iron absorption; do not use
within 1 to 2 hours of iron administration.
 Vitamin C and acidic foods increase iron absorption.
 Delayed release and enteric coated formulations are better tolerated, but are not as well
absorbed.
CALCIUM (CALCIUM CITRATE)
Calcium intake is especially crucial during pregnancy and lactation because of the potential
adverse effect on maternal bone health if maternal calcium stores are depleted.
Mechanism of Action
Calcium citrate increases plasma calcium levels. This reduces calcium flux from osteocyte
activity by reducing the secretion of parathyroid hormone (PTH). Calcium does this by
stimulating a G-protein coupled calcium receptor on the surface of parathyroid cells.
Indications:
 Low calcium levels such as bone loss (osteoporosis),
 Weak bones (osteomalacia/rickets),
 Decreased activity of the parathyroid gland (hypoparathyroidism),
 A certain muscle disease (latent tetany).
Contraindications:
 Cancer patients with bone metastasis
 Hypercalcemia
 Hypophosphatemia
 Renal calculi

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Adverse effects:
 Headache, Nausea or vomiting
 Irritability
 Hypercalcemia
 Chalky taste
Dosage and route of administration
1.5 g–2 g oral elemental calcium OD orally.
Preparation
 Tablet - 250mg, 500mg
Side effects of Calcium Citrate include:
 Low blood pressure (hypotension)
 Constipation
 Gas (flatulence)
 Belching
 Low blood phosphates (hypophosphatemia)
 Low blood magnesium (hypomagnesemia)
 Milk-alkali syndrome (very high, chronic dosing)
Nursing considerations
 Advise patient to take oral calcium 1 or 1.5 hours after meals if GI upset occurs
 Monitor calcium level if the patient is having mild renal impairment.
 Advice patient to report for any kind of abdominal pain, vomiting or nausea occurs.
 Coma
 Confusion
 Delirium
 Lethargy
 Loss of appetite

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ANTI-HYPERTENSIVE DRUGS
Drugs are essential when the BP is 160/110 mm of Hg to protect the mother from cerebral
hemorrhage, cardiac failure and placental abruption.
 Aim is to reduce BP to a mean < 125 mm Hg.
 Their benefit in mild moderate hypertension is not yet known.
 First line therapy Methyldopa or Labetalol.
 Second line drug is Nifedipine
 ACE inhibitors are avoided in pregnancy.
Here are the choices of drugs given during pregnancy are:
 Sympatholytics or Adregenic inhibitors: Methyldopa, Reserpine
 Alpha and Beta blockers or Adregenic blocking agent: Labetalol Hydrochloride,
Propranolol
 Calcium channel blockers: Nifedipine, Nicardipine
 Alpha blockers: Methyldopa
 Vasodilators: Hydralazine, Prazocin, Sodium Nitroprusside
Anti hypertensive drugs contraindicated in pregnancy:
 Poor fetal renal function
 Malformation or can cause IUGR.
METHYLDOPA
Methyldopa safely and successfully used to treat hypertension during pregnancy. It crosses the
placenta, and may cause mild hypotension in neonates of treated mothers.
Mechanism of Action
 Central and peripheral anti-adrenergic action.
 Inhibit the central vasomotor centre, decreasing sympathetic outflow to the heart, kidney
and peripheral vasculature.

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Indications
 Hypertension
 Hypertensive crisis
 Psychic patience
 Congestive cardiac failure.
 Effective and safe for both the mother and the fetus.
Contraindication:
 Pheochromocytoma (tumor of adrenal gland tissue)
 Anemia
 Depression
Dosage and routes of administration:
 Tablet: 250 mg BD or TID max 2g daily
 I V infusion: 250-500 mg
Adverse effects
 Decrease mental activity
 Sedation
 Headache or depression
Pharmacokinetics:
Absorption: GI tract, 50%
Metabolism: Liver
Excretion: Urine (70%), feces (30-50%)
Nursing considerations:
Assess
 Blood values: Neutrophils, platelets, CBC
 Renal studies: Protein, BUN, creatinine
 Bradycardia
 Hepatic necrosis
 Hepatitis
 Severe liver disease
 Decreased kidney function
 Lactating mother

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Liver function tests
 Blood pressure before beginning treatment and periodically thereafter.
Evaluate
 Decrease in blood pressure ( therapeutic response)
 Allergic reaction : Rash, fever, pruritis, urticaria
 Symptoms of congestive heart failure (edema, dyspnea, wet rales)
 Renal symptoms: Polyuria, oliguria, frequency of urine.
Teach Client /Family
 To avoid hazardous activities.
 Administer one hour before meals.
 Not to discontinue drug abruptly or withdrawal symptoms may occur.
 Not to use over the counter (OTC) medications (non-precription) for cough, cold or
allergy, unless directed by physician.
 Compliance with dosage schedule even if feeling better.
 Not to skip or stop drug unless directed by physician.
 Notify physician of untoward signs and symptoms.
LABETALOL HYDROCHLORIDE
It's used to treat high blood pressure in pregnancy. It can also be used to prevent chest pain
caused by angina. It helps to prevent future heart disease, heart attacks and strokes.
Mechanism of Action:
 Labetalol acts by blocking alpha and beta adrenergic receptors, resulting in decreased
peripheral vascular resistance without significant alteration of heart rate or cardiac output.
Indications:
 Hypertension

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Contraindications:
 Bronchial asthma
 Hepatic failure
 Heart failure
 Prolonged hypotension
 Severe Bradycardia
Dosage and route of administration:
 Orally: 100 mg TID can extend till 800 mg
 IV infusion: 1-2 mg
Adverse effects:
 Dizziness
 Fatigue
 Nausea or vomiting
 Headache
 Vertigo
Pharmacokinetics:
 Absorption: Absorbed from the GI tract.
 Metabolism: Liver, 100% bioavailability
 Excretion: Urine.
Nursing considerations:
 Input-output and weight daily
 Apical or radial pulse assessment before administration.
 Advised patient to remain in supine position for 3hrs after infusion.
 Monitor BP frequently.

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 In diabetic patient monitor glucose level closely.
 Advised patient that dizziness can be minimized by rising slowly and avoiding sudden
position change.
Teach Client / Family
 Not to discontinue drug abruptly.
 Not to use over the counter medications containing - adrenergic stimulants, such as
nasal decongestants and cold medications, unless directed by physician.
 To report bradycardia, dizziness, confusion or depression.
 To avoid alcohol, smoking and excess sodium intake.
 Take medication at bedtime to prevent the effect of orthostatic hypotension.
NIFEDIPINE
Nifedipine is an effective drug to treat severe hypertension in pregnancy and preterm labour.
Because it is given in a tablet or capsule by mouth, it is easier to use than intravenous drugs.
Mechanism of Action:
 Nifedipine is a type 2 calcium channel blocker that inhibits the inward flow of calcium
across the L‐type slow channels of cellular membranes.
 Its effect is primarily that of causing smooth muscle relaxation.
 Its applications have been in vascular, uterine and bladder smooth muscle relaxation.
Indication:
 Hypertension
 Angina pectoris
Contraindications
 Simultaneous use of magnesium sulphate
 Second or third degree heart block.

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Dosage and route of administrations
 Tablet: 5-10mg TID orally.
Side effects:
 Tachycardia
 Headache
 Methaemoglobinemia
 Inhibition of labor
 Fatigue
 Drowsiness
Pharmacokinetics:
Absorption: Absorbed rapidly from the GI tract after oral administration; however, only about
65-70% of drug reaches the systemic circulation.
Distribution: About 92% to 98% of circulating nifedipine is bound to plasma proteins.
Metabolism: Metabolized in the liver.
Excretion: Excreted in urine and feces as inactive metabolites.
Nursing considerations:
Assess
Blood levels of the drug, therapeutic levels 0.025 to 0.1 g/ml.
Administer
Before meals
Evaluate
Therapeutic response, Cardiac Status, BP, Pulse, Respiration and ECG.
Teach Client/Family
 To limit caffeine consumption
 To avoid OTC drugs unless directed by the physician
 Stress patient compliance to all aspects of drug use.
 Flushing
 Hypotension

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HYDRALAZINE
Hydralazine has been the recommended antihypertensive of first choice for severe hypertension
in pregnancy. Its side effects (such as headache, nausea, and vomiting) are common and mimic
symptoms of deteriorating pre-eclampsia.
Mechanism of Action:
 Hydralazine may interfere with calcium transport in vascular smooth muscle by an
unknown mechanism to relax arteriolar smooth muscle and lower blood pressure.
 The interference with calcium transport and prevent calcium release from intracellular
compartments. This decrease in vascular resistance leads to increased heart rate, stroke
volume, and cardiac output.
Indications
 Hypertension
 Heart failure.
Contraindications
 Coronary artery disease
 Rheumatic heart disease
 Stroke
 Severe renal impairment
 Mitral valvular rheumatic heart disease
 Inhibition of labour
Dosage and route of administration
 Orally - 100 mg / day in 4 divided doses
 IV / IM bolus 20 to 40 mg QID- 6h.
 Pruritis
 Neutropenia
 Leukopenia
 Neonatal: Thrombocytopenia
 Orthostatic hypotension

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Adverse effects
Maternal
Pharmacokinetics:
 Absorption: GI tract
 Metabolism: Significantly metabolized in liver
 Excretion: Urine (14% unchanged)
Nursing considerations
Assess
 BP every 15 minutes initially for 2 hours then every hour for 2 hours, and then QID ,
pulse QID
 Blood studies: Electrolytes, CBC and serum glucose
 Intake Output and weight daily
Administer
 To patient in recumbent position, keep in that position for one hour after administration.
Evaluate
 Edema in feet and legs daily.
 Skin and mucous membrane for hydration, Rales, dyspnea, orthopnea Joint pain,
tachycardia, palpitation, head ache and nausea.
Teach Client / Family
 To take with food to increase bio-availability.
 To notify physician if chest pain, severe fatigue, muscle or joint pain occurs.
 Advised patient to take drug after food to increase absorption.
 Hypotension
 Tachycardia
 Arrhythmia
 Palpitation
 Acute rheumatoid state
 Muscle cramps
 Headache

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PROPRANOLOL (INDERAL)
This drug is only recommended for use during pregnancy, when there are no alternatives and the
benefit outweighs the risk. Beta blockers may cause decreased placental perfusion, fetal and
neonatal bradycardia, and hypoglycemia.
Mechanism of Action
 - Adrenergic blocker: Decreases preload, afterload, which is responsible for decreasing
left ventricular end diastolic pressure and systemic vascular resistance.
Indications
 Hypertension
 Prophylaxis of angina pain.
Contraindications
 Bronchial asthma,
 Renal insufficiency
 Diabetes mellitus
 Cardiac failure
Dosage and Routes of Administration
 Orally 80-240 mg in divided doses BD/TID
Side Effects/Adverse Reactions
Maternal:
 Severe hypotension,
 Sodium retention,
 Bradycardia,
 Bronchospasm,
 Cardiac failure.
Fetal
 Bradycardia
 Impaired fetal responses to hypoxia
 IUGR with prolonged therapy
 Neonatal hypoglycemia

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Pharmacokinetics:
Absorption: Absorb in GI tract
Metabolism: Significantly metabolized in liver
Excretion: Urine
Nursing Considerations
Assess
 BP, pulse and respirations during therapy
 Weight daily and report excess weight gain - Intake output ratio.
Administer
 Administer with 240 ml of water on empty stomach.
Evaluate
 Tolerance if taken for long period Headache, light - headedness, decreased BP.
Teach Client / Family
 There may be stinging sensation when the drug comes in contact with mucous
membranes
 The drug may be taken before stressful activity exercise
 Client compliance with treatment regimen
 To make position changes slowly to prevent fainting.
PRAZOSIN
Prazosin is more slowly, but apparently more completely, absorbed during pregnancy and that its
half-life is slightly prolonged. Prazosin appears to be both effective and safe when
used during the last trimester to control blood pressure.
Mechanism of Action
 Prazosin is a competitive alpha-1 adrenergic receptor blocker. By blocking alpha-1
receptors on muscle cells that surround blood vessels, consequently decreases
the resistance of blood flow.

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 Selective post-synaptic blocker. Decreases plasma rennin activity.
Indications
Pregnant patients with moderately severe hypertension
Contraindications
 Affects on fetal normal development.
 During Lactation infant increases weight.
 Alternative drug can prescribe, especially during preterm and low birth weight infant.
Dosage and Routes of Administration
 Orally 1 mg BID, may be increased to 20mg/day
Side Effects/Adverse Reactions
 Dizziness.
 Headache, Nausea.
 Drowsiness.
 Lack of energy.
 Weakness.
 Palpitations.
Pharmacokinetics:
 Absorption: Through orally & absorb in GI tract
 Metabolism: Significantly metabolized in liver
 Excretion: This drug is mainly excreted in the bile and the feces.

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Nursing Considerations
 Reduce first dose, to avoid hypotension and syncope.
 Check Vital signs regularly.
 Strict salt diet.
NITROGLYCERINE
Intravenous nitroglycerin would appear to be an ideal agent for the treatment of
severe pregnancy-induced hypertension complicated by cardiogenic pulmonary edema.
Mechanism of Action
 Nitroglycerin infusion effectively reduces preload by venous dilatation and, at higher
doses, results in arterial vasodilatation.
Indications
 Pregnant patients reduces the workload of the heart
 Helps to relieve heart failure.
Contraindications
 Sensitivity to nitrate medications
 Hypotensive
 Increased intracranial pressure
 Severe anemia
Dosage and Routes of Administration
 Given as IV infusion 5 /min, increased at every 3-5 min upto 100 /min

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Side Effects/Adverse Reactions
 Tachycardia
 Headache
 Methaemoglobinemia
SODIUM NITROPRUSSIDE
Sodium Nitroprusside has been used to alter blood pressure in severe hypertensive disease of
pregnancy; however, concern exists in regard to potential lethal complications from cyanide
toxicity in both mother and fetus.
Mechanism of Action
As a result of its breakdown to nitric oxide (NO), sodium nitroprusside has potent vasodilating
effects on arterioles and venules (veins more than arteries) but this selectivity is much less
marked than that of nitroglycerin.
Indications
 Pregnant patients reduces the workload of the heart
 Helps to relieve heart failure.
Contraindications
 Patients with vitamin B12 deficiency,
 Anaemia,
 Severe renal disease or hypovolaemia
Dosage and Routes of Administration
 Given as IV infusion 0.25 - 8 /kg/min

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Side Effects/Adverse Reactions
Maternal:
 Dizziness
 Weakness
 Palpitations
 Vertigo
 Headaches
 Vomiting
 Sever Hypotension
Nursing Considerations
 Check Vital signs regularly.
 Strict salt diet.
 Assessment of clinical conditions.
 Advice mother to take medication during night times.
CAPTOPRIL
Captopril during the second and third trimesters of pregnancy harms the unborn baby's kidneys
and even increases the risk of death to the unborn baby.
Mechanism of Action
 Inhibit formation of Angitension II from Angitension I.
Indications
 Acute hypertension.
 Congestive heart failure.
 Left ventricular dysfunction after myocardial infarction.
 Diabetic nephropathy.
Fetal:
 Fetal Toxicity: due to Cyanide
and thiocynate.

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Contraindications
 Should be avoided during pregnancy.
 Suitable for chronic hypertension in non-pregnant state.
Dosage and Routes of Administration
 Orally 6.25 mg BID
Side Effects/Adverse Reactions
Maternal:
 Hypotension
 Headache
 Asthenia
 Arrhythmias
Nursing Considerations
 Check Vital signs regularly.
 Strict salt diet.
 Captopril should not be used during the second and third trimesters of pregnancy because
it may be harmful to a developing baby.
 It's not recommended in the first trimester unless considered essential by doctor.
DIURETICS
Diuretics are used in the following conditions during pregnancy:
 PIH with massive edema
 Eclampsia with pulmonary edema
 Severe anemia in pregnancy with heart failure
 Prior to blood transfusion in severe anemia
 As an adjunct to certain antihypertensive drugs.
Fetal:
 Oligohydromnios
 IUGR
 Fetal and neonatal renal failure

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FUROSEMIDE (LASIX)
LASIX should be used during pregnancy only if the potential benefit justifies the potential risk to
the fetus. Treatment during pregnancy requires monitoring of fetal growth because of the
potential risk for higher birth weights.
Mechanism of Action
Furosemide, like other loop diuretics, acts by inhibiting the luminal Na-K-Cl co-transporter in
the thick ascending limb of the loop of Henle, by binding to the chloride transport channel, thus
causing sodium, chloride, and potassium loss in urine.
Indications
 Acute pulmonary edema
 Hypertension
Contraindications
 Anuria
 Hepatic cirrhosis
 Allergic to sulfonamides
Dosage and routes of administration
 40 mg tablet, daily following breakfast for 5 days a week.
 In acute conditions, the drug is administered parenterally in doses of 40 - 120 mg daily.
Adverse effects
Fetal:
 Decreased leading to
fetal compromise
 Thrombocytopenia
 Hyponatraemia
Maternal:
 Weakness
 Fatigue
 Muscle cramps
 Hypokalemia

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Pharmacokinetics
 Absorption: Furosemide is absorbed from the gastrointestinal tract.
 Metabolism: it occurs mainly in the kidneys and the liver, to a smaller extent.
 Excretion: 43% of the drug undergoes renal excretion.
Nursing considerations
 Monitor weight, BP and pulse rate routinely for long term use.
 Monitor patient I/O chart.
 Watch the signs for hypokalemia such as muscle weakness and cramps.
 Monitor uric acid if patient is having gout.
 Advise the patient to take drug in the morning after food.
 Advised patient to avoid direct sunlight to prevent photosensitivity reactions.
TOCOLYTIC AGENTS
These drugs can inhibit uterine contractions & used to prolong the pregnancy. In women who
develop premature uterine contractions, in addition to putting them to absolute bed rest &
sedating. Tocolytic drugs are administered in an attempt to inhibit uterine contraction.
Here are the drugs used are:
 Betamimetics:
 Isoxuprine Hydrochloride
 Ritrodrine Hydrochloride
 Terbutaline
 Indomethacin
 Calcium channel Blockers
 Nifidepine
 Megnesium sulphate
 Oxytocin antagonists
 Atosiban

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 Nitric Oxide (NO) Donors:
BETAMIMETICS
Betamimetic (not comparable) mimics the stimulation of the beta-adrenergic receptors of the
sympathetic nervous system.
Mode of Action:
Activation of the intracellular enzymes [adenylate cyclase, cAMP, protein kinase] reduces
intracellular free calcium channel [Ca++] and inhibits the activation of MLCK (Myosin light-
chain kinase)
Indication:
 To prevent preterm delivery
 To prolong delivery
Contraindications:
 Severe pregnancy-induced hypertension,
 Eclampsia/preeclampsia,
 Active vaginal bleeding,
 Placental abruption,
 A cardiac disease
Dosage & Route of Administration:
 Ritodrine is given by IV infusion, 50 g / min. and increased by 50 g every 10 min.
until contractions cease. Maximum dose of 350 g / min. may be given. Infusion is
continued for about 12 hours after contraction cease.
 Terbutaline has longer half life and has fewer side effects. Subcutaneous injection of
0.25 mg every 3-4 hours is given.

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 Isoxurpine is given as IV drip 100 mg in 5D. Rate 0.2 g / minute. To continue for at
least 2 hours after contraction ceases. Maintenance is by IM 10mg six hourly for 24
hours, tab 10 mg 6-8 hourly.
Side effects:
Maternal:
 Headache
 Palpitation
 Tachycardia
 Pulmonary edema
 Hypotension
Neonatal:
 Hypoglycemia
 Intraventricular haemorrhage
Nursing considerations
 Assess Maternal & fetal heart tones during infusion and also Intensity & length of uterine
contractions
 Monitor Fluid intake to prevent fluid overload, discontinue if this occurs
 Positioning of patient in left lateral recumbent position to decrease hypotension &
increase renal blood flow.
 Advise patient to remain in bed during infusion.
INDOMETHACIN
Indomethacin is an appropriate first-line tocolytic for the pregnant patient in early preterm
labor (<30 wk) or preterm labor associated with polyhydramnios. A more significant
inflammatory response in the membranes and decidua is observed at gestational ages less than 30
weeks compared with 30-36 weeks.
 Lactic academia
 Hypokalemia
 Even death
 Cardiac failure
 Hyperglycemia
 ARDS
 Hyperinsulinemia


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Mechanism of Action:
Reduces synthesis of PGs, thereby reduces intracellular free Ca ++, activation of MLCK
(Myosin light-chain kinase) and uterine contractions.
Indications
 Preterm labor.
 Used alone or in combination with other tocolytics, such as magnesium sulfate.
 Effective in the second and early third trimesters.
Contraindications
 Heart attack
 High cholesterol
 High blood pressure
 Diabetes
Side Effects/Adverse effects
Mother:
 Dizziness
 Heartburn
 Nausea
 Vomiting
 Vaginal bleeding
 Excess amniotic fluid
 Inflamed stomach lining
Dosage and routes of administration
 Oral: 25 to 50 mg every 6 hours for 48 hours.
Fetal:
 Kidney problems
 Jaundice
 Necrotizing enterocolitis,
 Intraventricular hemorrhage

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Pharmacokinetics:
 Absorption: GI
 Metabolism: Hepatic, by both the mother and fetus
 Excretion: Not available
Nursing considerations
 Assess Maternal & fetal heart tones during infusion and also Intensity & length of uterine
contractions
 Monitor Fluid intake to prevent fluid overload, discontinue if this occurs
 Administer only clear solutions after dilution 150 mg in 500 ml D5W or NS, give at
0.3mg/ml By Using infusion pumps / monitor carefully.
 Positioning of patient in left lateral recumbent position to decrease hypotension &
increase renal blood flow.
 Advise patient to remain in bed during infusion.
MAGNESIUM SULFATE
Magnesium sulfate therapy is used to prevent seizures in women with pre-eclampsia. It can also
help prolong a pregnancy for up to two days. This allows drugs that speed up your baby's lung
development to be administered.
Mechanism of Action:
 To trigger cerebral vasodilation, thus reducing ischemia generated by cerebral vasospasm
during an eclamptic event.
 The substance also acts competitively in blocking the entry of calcium into synaptic
endings, thereby altering neuromuscular transmission.
 Direct depressant action on the uterine muscle.

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Indication:
 Prevent seizures in preeclampsia
 Control of seizures in eclampsia,
 Use for preterm labor is off-label
Contraindication:
 Myasthenia gravis
 Impaired renal function.
 Hypersensitivity
 Hypermagnesemia
 Hypercalcemia
 Administration during 2 hours preceding delivery for mothers with toxemia of pregnancy.
Side Effects/ Adverse effects:
Maternal:
 Flashing
 Perspiration
 Headache and muscle weakness
 Rarely pulmonary oedema
Dosage & Route of Administration
 Initial dosage: 4-6 gm in I.V infusion (10-20% solution) over 20-30 min followed by an
infusion of 1-2 gm/hr.
 Continue for 12 hrs as the contractions stopped.
Pharmacokinetics:
 Absorption: Given I.V. and I.M.
 Distribution: Distributed widely throughout the body.
Fetal:
 Lethargy
 Hypotonia
 Rarely respiration depression.

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 Metabolism: None.
 Excretion: Excreted unchanged in urine; some appears in breast milk.
Nursing Consideration:
 Monitor Vital signs.
 Monitor newborn for hypotension, hyporeflexia, and respiratory depression.
 Monitor intake and output ratios.
 Lab Test Considerations: Monitor serum magnesium levels and renal function
periodically throughout administration of parenteral magnesium sulfate.
 Advice mother to increase intake of fluids.
 Advice mother to report during side effects of magnesium sulfate.
OXYTOCIN RECEPTOR ANTAGONISTS
Oxytocin receptor antagonists (ORA), such as Atosiban, have been specially developed for the
treatment of preterm labour. ORA have been proposed as effective tocolytic agents for women in
preterm labour to prolong pregnancy with fewer side effects than other tocolytic agents.
Mechanism of Action:
 Atosiban is primarily an arginine vasopressin (AVP) V1a receptor antagonist with lower
affinity for the OTR.
 Its action is via dose-dependent inhibition of OT-mediated increase in intracellular
calcium levels which involves closing of voltage gated channels to prevent influx of
calcium.
 It inhibits intracellular calcium release, release of PGS and thereby inhibits myometrial
contractions.

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Indication:
 Prevent preterm labor
 Immature birth by suppressing uterine contractions
Contraindication:
 Gestational age: < 24 or > 33 completed wks.
 Intrauterine fetal death
 Suspected intrauterine infection (chorioamnionitis)
 PROM > 30 wks of gestation
 Placenta praevia, Abruptio placenta.
 Abnormal foetal heart rate
 Antepartum uterine hemorrhage
 Eclampsia & severe pre – eclampsia
 Hypersensitivity to the atosiban or excipients.
Side Effects/ Adverse effects:
Maternal:
 Dizziness
 Headache
 Hot flush
 Hyperglycaemia
 Hypotension
 Nausea & vomiting
 Tachycardia
Dosage & Route of Administration
 300 in I.V infusion. Initial bolus may be needed.
Fetal:
 Hyporeflexia
 Respiratory distress
 Hypotension

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Pharmacokinetics:
 Absorption: Given I.V. and I.M.
 Distribution: Distributed widely throughout the body.
 Metabolism: None.
 Excretion: Excreted unchanged in urine; some appears in breast milk.
Nursing Consideration:
 Monitor Vital signs.
 Monitor newborn for hypotension, hyporeflexia, and respiratory depression.
 Monitor intake and output ratios.
 Advice mother to increase intake of fluids.
OXYTOCICS
Oxytocics are the drugs that have the power to excite contractions of the uterine muscles. Among
a large number of drugs belonging to this group the ones that are important and extensively used
are:
 Oxytocin
 Ergot derivatives
 Prostaglandins
OXYTOCIN
Oxytocin is a nonapeptide. It is synthesised in the supraoptic and paraventricular nuclei of the
hypothalamus. By nerve axons it is transported from the hypothalamus to the posterior pituitary
where it is stored and eventually released.
Oxytocin has a half life of 3-4 minutes and duration of action of approximately 20 minutes.
It is rapidly metabolized and degraded by oxytocinase.

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MODE OF ACTION:
 Myometrial oxytocin receptor concentration increases maximum (100 - 200 fold) during
labour.
 Oxytocin acts through receptor and voltage mediated calcium channels to initiate
myometrial contractions.
 It stimulates amniotic and decidual prostaglandin production.
 Bound intracellular calcium is eventually mobilised from the sarcoplasmic reticulum to
activate the contractile protein.
 Acts directly on myofibrils producing uterine contractions stimulates milk ejection by the
breasts
 The uterine contractions are physiological i. e. causing fundal contraction with relaxation
of the cervix.
PREPARATIONS
 Synthetic oxytocin (Syntocinon - Sandoz or Pitocin - Parke Davis) is widely used. It has
only got oxytocic effect without any vasopressor action.
 Syntocinon is available in ampoules containing 5 IU / ml: (Pitocin 5 IU / ml).
 Syntometrine (Sandoz) - A combination of syntocinon 5 units and ergometrine 0.5 mg
 Desamino oxytocin - It is not inactivated by oxytocinase and is 50 - 100% more effective
than oxytocin. It is used as buccal tablets containing 50 L.U.
 Oxytocin nasal solution contains 40 units / ml.
INDICATIONS:
Oxytocin may be conveniently used in pregnancy, labour or puerperium. The indications are
grouped as follows:
 Therapeutic
 Diagnostic

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Therapeutic:
Pregnancy
Labour
Puerperium
Pregnancy: Early
 To accelerate abortion - inevitable or missed and to expedite expulsion of hydatidiform
mole.
 To stop bleeding following evacuation of the uterus
 Used as an adjunct to induction of abortion along with other abortifacient agents (PGE, or
PGE2)
Late:
 To induce labour
 To facilitate cervical ripening for effective induction
 Augmentation of labour
 Uterine inertia
Labour:
 In active management of third stage, it is used along with ergometrine (Syntometrine)
during labour crowning of the head.
 Following expulsion of placenta as an alternative to ergometrine
Puerperium:
 To minimise blood loss and to control postpartum haemorrhage.
Contraindications
In late pregnancy
 Grand multipara
 Contracted pelvis
 History of LSCS or hysterectomy
 Malpresentation

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During labour
 Obstructed labour
 Incoordinate uterine action
Fetal
 Fetal distress,
 Uterine hypertonia or polysystole causes reduced placental blood flow.
DOSAGE & ROUTES OF ADMINISTRATION
 Controlled IV infusion (10 units of oxytocin in 1 of RL/5 % Dextrose)
 Nasal spray for milk let down process.
 IV Bolus or IM: 5-10 units after the birth of the baby as an alternative to ergometrine.
 Intramuscular - the preparation used is syntometrine
 Buccal tablets or nasal spray: Limited use on trial basis.
SIDE EFFECTS/ADVERSE EFFECTS
Maternal:
 Hypertonic uterine activity
 Uterine rupture
 Hypotension
 Water retention & water intoxication
Fetal:
 Fetal distress & fetal death
 Neonatal jaundice
PHARMACOKINETICS:
 Absorption: Administered I.V. and I.M
 Distribution: Distributed throughout the extracellular fluid; small amounts may enter the
fetal circulation.

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 Metabolism: Metabolized rapidly in the kidneys and liver. In early pregnancy, a
circulating enzyme, oxytocinase, can inactivate the drug.
 Excretion: Only small amounts are excreted in the urine as oxytocin. Half-life is 3 to 5
minutes.
DIAGNOSTIC:
Contraction stress test (CST) (Syn: Oxytocin challenge test)
It is an invasive method to assess the fetal well being during pregnancy. When there is
alteration in FHR in response to uterine contractions, it suggests fetal hypoxia.
Principles: The test is based on determination of the respiratory function of the feto-placental
unit during induced contractions when the blood flow through the unit is curtailed.
Objective: To detect the degree of fetal compromise so that a suitable time can be selected to
terminate the pregnancy.
Candidates for CST:
 Intrauterine growth restriction
 Postmaturity
 Hypertensive disorders of pregnancy
 Diabetes.
Contraindications:
 Compromised fetus
 Previous history of Caesarean section
 Complications likely preterm labour
 APH.
Procedure: The initial rate of infusion is 1 mU/minute which is stepped up at intervals of 20
minutes until the effective uterine contractions are established (vide supra). The alteration of the
FHR during contractions is recorded by electronic monitoring. Alternatively, clinical monitoring
can effectively be performed using hand to palpate the hardening of the uterus during contraction

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and auscultation of FHR during contraction and for one minute thereafter. It takes at least 1-2
hours to perform the test.
Importance: A negative test is associated with good fetal outcome. Whereas a positive CST is
associated with increased incidence of IUD, fetal distress in labour and low Apagar scores. But
there is 50 % chance of false positive results and as such positive test cases are subjected to other
methods of evaluating the well being of the fetus.
Nipple stimulation test: The woman stimulates uterine contractions for CST by rubbing the
nipple through her clothes for 10 minutes. It takes less time compared to CST.
Oxytocin sensitivity test (OST)
The test was devised by Nixon and Smith to assess the irritability of the uterus following the
administration of oxytocin.
Procedure: 0.01 units of oxytocin is injected intravenously at the end of a spontaneous uterine
contraction. The injection is to be administered at one minute intervals until an induced
contraction starts. This can be evidenced by hardening of the uterus on abdominal palpation.
Inference: If the contraction fails to start even after 4 injections, the uterus is unlikely to be
responsive to induction. Prediction of maturity of the fetus using the test is not reliable.
METHODS OF ADMINISTRATION
 Controlled intravenous infusion • Intramuscular
Controlled Intravenous Infusion:
Oxytocin infusion should be ideally by infusion pump. Fluid load should be minimum. It is
started at low rates (1-4 mU/min) and increased gradually.
 For induction of labour • Use in labour
For induction of labour
Principles:
 The oxytocin should be started with a low dose but escalated quickly where there is no
response. When the optimal response is achieved (uterine contraction sustained for about

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45 seconds and numbering 3 contractions in 10 minutes), the administration of the
particular concentration in mU/per minute is to be continued. This is called oxytocin
titration technique.
 The objective of oxytocin administration is not only to initiate effective uterine
contractions but also to maintain the normal pattern of uterine activity till delivery and at
least 30-60 minutes beyond that.
Calculation of the infused dose:
Now-a-days the infusion is expressed in terms of milliunits per minute. This can give an accurate
idea about the exact amount administered per minute irrespective of the concentration of the
solution.
Regulation of the drip: The drip is regulated by:
 Manually, counting the drops per minute commonly practiced.
 Oxytocin infusion pump which automatically controls the amount of fluid to be infused.
Convenient regime:
 It is a sound practice to start with a low dose (4 mU / minute) and to escalate at every 20
min. intervals if there is no response.
 The patient should preferably lie on one side or in semi-Fowler's position to minimise
venacaval compression.
 In majority of cases, a dose of less than 16 milliunits per minute (2 units in 500 ml Ringer
solution with drop rate of 60/minute) is enough to achieve the objective.
 Conditions where fluid overload is to be avoided infusion with high concentration and
reduced drop rate is preferred.
 However, in an unresponsive state, higher doses may be required specially when
induction is done in lesser weeks of gestation or in cases of intrauterine fetal death.
 Adequate uterine contractions are generally achieved with a concentration of 16-32
mIU/min.

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Use in labour:
 Uterine inertia or for augmentation of labour or in the active management of labour.
 The procedure consists of low rupture of the membranes followed by oxytocin infusion
when the liquor is clear.
 Feto-pelvic disproportion must be ruled out before hand.
Observation during oxytocin infusion:
 Rate of flow of influsion by counting the drops per minute or monitoring the pump.
 Uterine contractions number of contractions per 10 min, duration of contraction and
period of relaxation are noted. ‘Finger tip' palpation for the tonus of the uterus in between
contractions may be done where gad gets are not available.
 Peak intra uterine pressure of 50-60 mm Hg with a resting tone 10-15 mm Hg is optimum
when intra sitzrine pressure monitoring is used.
 FHR monitoring is done by auscultation at every 15 min interval or by continuous EFM.
 Assessment of progress of labour.
Indications of stopping the infusion:
 Nature of uterine contraction:
Abnormal uterine contractions occurring frequently (every 2 minutes or less) or
lasting more than 60 sec (hyperstimulation).
Increased tonus in between contractions.
 Evidences of fetal distress.
 Appearance of untoward maternal symptoms.
NURSING CONSIDERATIONS
Assess
 Intake and output ratio
 Uterine contractions and FHR
 Blood pressure , pulse and respiration

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Administer
 By IV infusion
 After having crash cart (emergency trolley) available in the ward.
Evaluate
 Length and duration of contractions
 Notify physician of contractions lasting over one minute or absence of contractions.
Teach Client/Family
 To report increased blood loss, abdominal cramps or increased temperature.
ERGOT DERIVATIVES
Ergometrine, also known as ergonovine, is a medication used to cause contractions of the uterus
to treat heavy vaginal bleeding after childbirth.
NOTE
 Ergometrine & Methergine can be used parenterally or orally.
 As the drug produces titanic uterine contractions, it should only be used after delivery of
the anterior shoulder or following delivery of baby.
 It should not be used in induction of labor or abortion.
 Syntometrine should always be administered IM.
MECHANISM OF ACTION
 Semi-synthetic ergot alkaloid-bromocriptine, an amino acid alkaloid has also frequently
been used in obstetrics to inhibit puerperal lactation.
 It is a partial dopamine agonist and antagonist in various CNS areas and inhibits prolactin
secretion induced by α-ergocryptines.
 Ergometrine acts directly on the myometrium. It stimulates uterine contractions &
decreases bleeding.

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INDICATIONS
Therapeutic
 To stop the atonic uterine bleeding following delivery, abortion/expulsion of
hydatidiform mole.
Prophylactic
 As a prophylaxis against excessive hemorrhage, it may be administered after the delivery
of the anterior shoulder with crowing/following delivery of baby.
CONTRAINDICATIONS:
The following are contraindications to its use:
Prophylactic:
 Suspected plural pregnancy: If given accidentally with the delivery of the first baby, the
second one is likely to be compromised by the tetanic contraction of the uterus.
 Organic cardiac diseases: It may cause sudden squeezing of blood of the uterine
circulation into the general circulation causing overloading of the right heart and
precipitating failure.
 Severe pre - eclampsia and eclampsia: There may be sudden rise of blood pressure.
 Rh - negative mother: There is more chance of feto - maternal micro-transfusion.
Therapeutic:
 Heart disease or severe hypertensive disorders: because of its vasoconstrictive effect,
it may cause transient hypertension specially when given intravenously.
DOSAGE AND ROUTES OF ADMINISTRATION
 For active management of 3rd stage of labour - 0.2mg (amp) to be given IM.
 For control of atonic PPH - slowly over 60 seconds may be repeat after 2hrs.
 For excessive lochia and subinvolution - 1 Tablet (0. 125mg) TDS for 3 days.

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PREPARATIONS
 Ergometrine - 0. 25mg/0.5mg ampoules & 0.5 - 1mg tablets
 Methergine - 0.2 mg ampoules & Tablets: 0.5 - 1mg
 Syntometrine Ergometrine - 0.5 mg + syntocinon 5 units ampoule.
ADVERSE EFFECTS
 Ergot poisoning: Gangrene, Vision problems, Confusion, Convulsions,
Unconsciousness, and death.
 Due to vasoconstrictive action: Precipitate rise of blood pressure, Myocardial
Infraction, Stroke, Bronchospasm.
 Interference with lactation.
NURSING CONSIDERATIONS
 Assess patient BP, pulse, respiration, signs of hemorrhage
 Administer Orally/ IM deep, have emergency cart readily available
 Evaluate for decrease blood loss
 Advised patient to report for increased blood loss, abdominal cramps, headache,
sweating, nausea, vomiting/ Dyspnea.
PROSTAGLANDINS
Prostaglandins are the derivates of prostanoic acid from which they derive their names.
Chemistry:
Prostaglandins are 20 carbon carboxylic acids with a cyclopentane ring which are formed from
polyunsaturated fatty acids of the many varieties of prostaglandin, PGE2, and PGF2 are
exclusively used in clinical practice. The subscript numeral after the letter indicates the degree of
unsaturation. Inactivation in done in lungs and liver.

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Source:
Prostaglandins are synthesized from one of the essential fatty acids, archidonic acid, which is
widely distributed throughout the body.
In the female, these are identified in the menstrual fluid, endometrial, decidua & amniotic
membrane.
MODE OF ACTION
 Both PGE2 & PGF2 alpha have an oxytocic effect on the pregnant uterus.
 They also sensitize the myometrium to oxytocin.
 PGF2 alpha acts predominantly on the myometrium, while PGE2 acts mainly on the
cervix.
INDICATIONS
 For induction of abortion during 2nd trimester & expulsion of hydatidiform mole.
 For induction of labor in IUD of fetus
 In augmentation / acceleration of labor.
 To stop bleeding from the open uterine sinuses as in refractory cases of atonic PPH
 Cervical ripening prior to induction of abortion or labour.
CONTRAINDICATIONS
 Hypersensitivity to the compound
 Uterine fibroids
 Cervical stenosis
 PID
 Uterine scar

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DOSAGE & ROUTES OF ADMINISTRATION
Prostaglandin E2 is widely used because it is less toxic and more effective than PGF2 .
 Tablet: Contains 0.5 mg Dinoprostone (Prostin E2)
 Vaginal suppository: Containing 20 mg PGE2 or 50 mg PGF2 in a lipid base.
 Vaginal Pessary: Containing 3 mg PGE2.
 Prastin E2 (Dinoprostone) gel: 500 g into the cervical canal, below the level of internal
os or 1-2 mg in the posterior forni.
Parenteral
 PGE2: Prostin E2 containing 1 mg / ml.
 PGF2 : Prostin F2 (Dinoprost tromethamine) containing 5 mg / ml.
 Methyl Analogue of PG F2 (Carboprost): 2.5 mg/10ml
SIDE EFFECTS/ADVERSE EFFECTS:
 Headache
 Dizziness
 Hypertension
 Muscle cramps
 Joint swelling
NURSING CONSIDERATIONS
 Assess patient RR , rhythm & depth , vaginal discharge, itching / irritation
 Administer Antiemetic/antidiarrheal preparations prior to giving this drug, high in vagina,
after warming the suppository by running warm water over package
 Evaluate patient for length & duration of contractions, notify physician of contractions
lasting over 1 minute or absence of contractions, fever & chills
 Advised patient to remain supine for 10-15 minutes after vaginal insertion.

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ANTICONVULSANTS
Convulsion in pregnancy is largely due to eclampsia. Other causes are- Epliepsy, Menengitis,
Cerebral malaria and cerebral tumours.
MAGNESIUM SULPHATE
Magnesium sulfate therapy is used to prevent seizures in women with preeclampsia. It can also
help prolong a pregnancy for up to two days. This allows drugs that speed up your baby's lung
development to be administered.
Mechanism of Action
 Decreased acetylcholine in motor nerve terminals, which is responsible for
anticonvulsant properties, thereby reduces neuromuscular irritability.
 It also decreases intracranial edema & helps in diuresis.
 Its peripheral vasodilatation effect improves the uterine blood supply. It has depressant
action on the uterine muscles & CNS.
Indications
 It is a valuable drug lowering seizure threshold in women with pregnancy - induced
hypertension.
 Used in preterm labor to decrease uterine activity.
Contraindications
 Impaired renal function
 Hypersensitivity
 Myocardial damage
 Hypermagnesemia
 Hypercalcemia

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Dosage & routes of administration
 For control of seizures: 20 ml of 20 % solution slowly in 3 - 4 mins , to be followed
immediately by 10ml of 50 % solution IM & continued 4 hourly till 24 hours postpartum
. Repeat injections are given only if knee jerks are present, urine output exceeds 100 ml
in 4 hours & respiration is more than 10 / minute. The therapeutic level of serum
magnesium is 4 - 7 mEq / L
 4gm IV slowly over 10 min , followed by 2 gm / hr and then 1gm / hr in drip of 5 %
dextrose for tocolytic effect.
Adverse effects ·
Maternal
 Severe CNS depression
 Evidence of muscular paresis
Fetal
 Tachycardia
 Hypoglycemia
Nursing considerations
 Assess patients Vital signs 15 min after IV dose, do not exceed 150 mg/min.
 Monitor magnesium level If using during labour, time of contractions, determine
intensity
 Urine output should remain 30 ml / hr or more if less notify physician
 Examine patient Reflexes - knee jerk, patellar reflex.
 Administer Only after calcium gluconate is available for treating magnesium toxicity
 Using infusion pump/monitor carefully, IV at less than 150mg/min, circulatory collapse
may occur
 Provide Seizure precautions: place client in single room with decreased stimuli , padded
side rails

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 Positioning of client in left lateral recumbent position to decrease hypotension &
increased renal blood flow.
 Evaluate patient Mental status, sensorium, memory, Respiratory status & Reflexes.
 Discontinue infusion if respirations are below 12 / min, reflexes severely hypotonic, urine
output below 30ml/ hr or in the event of mental confusion / lethargy / fetal distress.
DIAZEPAM (VALIUM)
Valium (diazepam) is a benzodiazepine derivative. Diazepam is a benzodiazepine that exerts
anxiolytic, sedative, musclerelaxant, amnestic effects.
Mechanism of Action
Depresses subcortical levels of CNS.
Indications:
 Eclampsia or Pre-eclampsia
 Seizures
 Anxiety in mothers
Contraindications:
 Severe respiratory insufficiency
 Myasthenia gravis
 Sleep apnea syndrome
 Severe hepatic insufficiency.
Dosage and Route of Administration
 Orally: 2 to 10 mg TID or QID
 Parentarally: 5 to 20 mg (bolus), 2 mg/min, may repeat after 5-10min, Maximum
doasage 60 mg, may repeat in 30 min if seizures reappear.

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Side Effects Mother:
Mother:
 Hypotension
 Dizziness
 Drowsiness
 Headache.
Pharmacokinetics:
Distribution: Diazepam and its metabolites cross the blood-brain and placental barriers and are
also found in breast milk in concentrations.
Metabolism: Diazepam and its metabolites are highly bound to plasma proteins.
Excretion: Excreted mainly in the urine.
Nursing Considerations:
Assess:
 BP in lying and standing positions; if systolic pressure falls 20 mmHg, hold drug and
inform physician
 Blood studies : CBC
 Hepatic studies.
Administer:
 IV into large vein to decrease chances of extravasation.
 PO with milk or food to avoid GI symptoms.
Evaluate:
Therapeutic response:
 Mental status,
 Sleeping pattern
 Physical dependence,
Fetus:
 Respiratory depressant effect,
 Hypotonea
 Thermoregulatory problems in newborn.
 Headache
 Nausea
 Vomiting

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Teach Patient / Family
 That drug may be taken with food
 To avoid alcohol ingestion
 Not to discontinue medication abruptly
 To rise slowly as fainting may occur.
PHENYTOIN (DILANTIN)
Maternal use of anti-seizure medications such as phenytoin, which is often used to treat epileptic
seizures, can result in multiple effects on the developing embryo and fetus, including fetal
hydantoin syndrome. The specific amount of phenytoin ingestion required to cause the disorder
has not been determined.
Mechanism of Action
Inhibits spread of seizure activity in motor cortex.
Indication:
 Eclampsia or Pre-eclampsia
 Seizures
Contraindication:
 Risk of fetal hydantoin syndrome
 Fetal bleeding
Dosage and Route of Administration
 Eclampsia: 10 mg / kg IV at the rate not more than 50 mg followed 2 hours later by
5 mg/kg
 Epilepsy: 300 to 400 mg daily orally in divided doses.

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Side Effects
Maternal
 Hypotension
 Cardiac arrhythmias
 Phlebitis at injection site
Fetal
 Mental Retardation
 Microcephaly
 Growth Deficiency
Nursing Considerations
Assess:
 Blood studies : CBC, platelets every 2 weeks until stabilized
 Discontinue drug if neutrophils < 1600/mm
Administer
 After diluting with normal saline
Evaluate
 Mental status , sensorium, memory
 Respiratory depression
 Blood dyscrasias: Sore throat, bruising.
Teach Patient / Family
 All aspects of drug administration, when notify physician.
PHENOBARBITONE (LUMINAL)
This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus.
The drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the
patient should be apprised of the potential harm to the fetus.

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Mechanism of Action
Decreases impulse transmission and increases seizure thresholds at cerebral cort level.
Indication:
 Eclampsia or Pre-eclampsia
 Seizures
Contraindications:
 Increased seizure
 Fetal malformation
Dose and Route of Administration
120 to 240 mg/day in divided doses.
Side Effects
Maternal
 Sedation
 Drowsiness
 Hangover
 Headache
 Hallucinations
Fetal
 Withdrawal syndrome.
Nursing Considerations
Assess
 Blood studies , liver function tests during long-term treatment
 Therapeutic level 15 to 40 mg/ml

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Evaluate
 Mental status, mood, senorium, affect and memory
 Respiratory depression
Teach Patient / Family
 All aspects of drug administration and when to notify physician.
ANTICOAGULANTS
HEPARIN SODIUM
Heparin, also known as unfractionated heparin, is a medication and naturally occurring
glycosaminoglycan. As a medication it is used as an anticoagulant. Specifically it is also used in
the pregnancy, treatment of heart attacks and unstable angina. It is given by injection into a vein
or under the skin.
Mechanism of Action
Heparin binds to the enzyme inhibitor antithrombin III (AT), causing a conformational change
that result in its activation through an increase in the flexibility of its reactive site loop. The
activated AT then inactivates thrombin, factor Xa and other proteases. Prevents conversion of
fibrinogen to fibrin.
Indications
 Deep vein thrombosis,
 Thromboembolism
 Disseminated intravascular coagulation
 Patients with prosthetic valves in the heart.
Contraindication:
 An increased risk of a clot forming during pregnancy or after birth.
 Recurrent thrombosis.

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Dosage and Routes
 Parentally: Initially 5,000 to 7,000 IU to be administered as IV push.
 In case of failure of initial dose by 2,500 units subcutaneously every 24 hours.
Side Effects
 Leukopenia
 Thrombocytopenia
 Osteoporosis
 Hemorrhage
 Alopecia
Nursing Considerations
Assess
 Blood studies: Hematocrit, platelets, occult blood in stools, Partial prothrombin time
 Blood pressure: Signs of hypertension.
Administer
 At same time, each day to maintain steady blood levels
 Avoid all IM injections that may cause bleeding.
Evaluate
 Therapeutic response: Decrease of deep vein thrombosis
 Bleeding gums, petechiae, ecchymosis, black tarry stools, hematuria
 Fever, skin rash urticaria
Teach Patient/Family
 To avoid use of drugs unless prescribed by physician
 To use soft bristle toothbrush to avoid bleeding gums
 To comply with instructions
 To recognize and to sign of bleeding - gums, under skin, urine, stool.

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WARFARIN SODIUM (COUMADIN)
Warfarin is an anticoagulant (blood thinner). Warfarin reduces the formation of blood clots.
Warfarin is used to treat or prevent blood clots in veins or arteries, which can reduce the risk
of stroke, heart attack, or other serious conditions.
Mechanism of Action
Interferes with blood clotting by indirect means-depresses hepatic synthesis of vitamin K-
dependent coagulation factors (II, VII, IX, X).
Indications
 Deep vein thrombosis,
 Pulmonary embolism.
Contraindication:
 Recent brain, eye, or spinal cord injury or surgery.
 Severe liver or kidney disease.
 Uncontrolled hypertension.
 Crosses placenta and may cause fatal hemorrhage in the fetus.
Dosage and Route
 Tablets: 10 to 15 mg orally daily for 2 days,
 Followed by 2-10 mg at the same time each day depending upon the prothrombin time.
Side Effects
Maternal
 Hemorrhage.
 Optic atrophy
Fetal:
 Fetal Skeletal and facial
deformities
 Microcephaly.


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 Allergic reactions
 Liver problems
 Low blood pressure
 Swelling
 Low red blood cells
 Paleness
 Fever
Pharmacokinetics:
 Absorption: Completely absorbed from the GI tract.
 Metabolism: Liver
 Excretion: 80% of the total dose is excreted in the urine with the remaining 20% appearing in
the feces.
Nursing Considerations
Assess
 Blood studies: Hematocrit, platelets, occult blood in stools
 Prothrombin time BP: Watch for signs of hypertension.
Administer
 At same time, each day to maintain steady blood levels
 Alone do not give with food
 Avoid all IM injections that may cause bleeding.
Perform / Provide
 Storage in tight container.
Evaluate
 Therapeutic response: Decrease of deep vein thrombosis
 Bleeding gums, petechiae, ecchymosis, black tarry stools, hematuria, fever, skin rash,
urticaria.

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Teach Patient / Family
 To avoid over the counter (OTC) preparations unless prescribed by physician
 Drug may be held during menstruation
 To use soft - bristle tooth brush Stress client compliance
 To report any sign of bleeding.
ANALGESICS
VALETHAMATE BROMIDE (EPIDOSIN)
The importance of cervical dilatation in normal labour is well known & cervical dystocia is
known to prolong labour adversely affecting fetomaternal well being. Valethemate bromide
(Epidosin) has been known to shorten the first stage of labour. It is also used as Cervical
Spasmodics.
Mechanism of Action
It is both central and peripheral antimuscarininc agent, which is a competitive inhibitor of
acetylcholine at the muscarinic receptor.
Indication
 Cervical dilatation in the first stage of labor
 Symptomatic relief of GI tract and ureteric colic.
Contraindications
 Paralytic ileus
 Myasthemia Gravis
 Hypertension
 Ulcerative colitis
 Closed angle glaucoma
 CVS disorders

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Adverse effects
 Dryness of mouth
 Thirst
 Dilatation of pupil
 Palpitations
 Giddiness
Dosage and routes of administration
Injection - 8mg deep IM. It may be repeated after 4 hours if necessary.
Nursing considerations
 Advise patient to report for any blurred vision, giddiness, dry mouth immediately.
 Advise patient to get up from the bed carefully and slowly.
TRAMADOL HYDROCHLORIDE
It is important to appropriately treat pain in pregnancy. For some women with severe pain,
treatment with tramadol in pregnancy might be considered the best option. Recreational (social)
use of tramadol in pregnancy is not advised.
Mechanism of Action
Bind to opioid receptor and inhibit reuptake of norepinephrine and serotonin
Indications
 Moderate to moderately severe pain.
 Safe given during labor as it does not cause depression to fetal respiratory centre and
hence safe for baby.

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Contraindications
 Breast feeding mothers
 Hypersensitiviy
 Hepatic impairment
 Increased ICP
Adverse effects
 Dizziness
 Headache
 Malaise
 Hypertonia
 Nausea or vomiting
Dosage and routes of administration
Tablet: 50 to 100mg 6 hourly or as required.
Injection: 50mg BD
Nursing considerations
 Monitor patient CV and respiratory status
 Monitor patient at risk for seizure
 Monitor patient bowel and bladder function.
PETHIDINE (MEPERIDINE)
It is synthetic narcotic analgesic agent, well absorbed by all routes of administration. As with all
drugs Pethidine Injection should only be given in pregnancy if absolutely necessary. Pethidine
can pass through placenta (during pregnancy and labour) or through your breast milk. Pethidine
Injection may cause breathing problems in newborns.

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Mechanism of Action
 Inhibits ascending pain pathways in central nervous system, increases pain threshold and
alters pain perception.
Indications
 Moderate To Severe Pain In Labor,
 Postoperative Pain,
 Abruptio Placentae,
 Pulmonary Edema
Contraindication
 Pethidine should not be used intravenously within 2 hours and intramuscularly within 3
hours of the expected time of delivery of the baby, for fear of birth asphyxia.
 It should not be used in cases of preterm labor and when the respiratory reserve of the
mother is reduced.
Dosage and Route of Administration
 Injectable preparation contains 50 mg/ml, can be administered SC, IM, IV. Its dose is 50
to 00 mg
 IM combined with promethazine 25 mg.
Side Effects / Adverse Reactions
Mother
 Drowsiness,
 Dizziness,
 Confusion,
Fetus
 Respiratory depression Birth asphyxia.
 Headache,
 Sedation,
 Euphoria,
 Nausea and Vomiting.

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Nursing Considerations
Assess
 Urinary Output: May cause urinary retention.
Administer
 With antiemetic (promethacin) to prevent nausea and vomiting
 When pain is beginning to return - Determine dosage interval by patient response
Perform/Provide
 Storage in light: Resistant container at room temperature
 Assistance with ambulation
 Safety measures: Side rails, night light, call bell within easy reach.
Evaluate
 Therapeutic response: Decrease in pain
 CNS changes: Dizziness, drowsiness, euphoria
 Allergic reactions: Rash, urticaria.
 Respiratory depression, notify physician if respirations are < 12/minute.
Teach Patient / Family
 To report symptoms of CNS changes , allergic reactions .
FENTANYL
Fentanyl is a synthetic narcotic analgesic agent. Fentanyl is a synthetic opioid analgesic more
potent than morphine.
Mechanism of Action
 Inhibits ascending pain pathways in CNS, increases pain threshold and alters pain
perception.
Indications
 Moderate to severe pain in labor, postoperative pain and as adjunct to general anesthetic

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Contraindications
 Hypersensitivity to opiates.
Dosage and Routes
 Injection: 0.05-0.1mg/ml/BD
Side Effects/Adverse
 Reactions Dizziness,
 Delirium,
 Muscle Rigidity,
 Blurred Vision.
Nursing Considerations
Assess
 Vital signs
 Note muscle rigidity.
Administer
 By injection (IM-IV), give slowly to prevent rigidity
 Only with resuscitative equipment available
Perform / Provide
 Storage in light resistant container at room temperature
 Coughing, turning and deep breathing for postoperative patients
 Safety measures: Side rails, night light, call bell within reach.
Evaluate
 CNS changes: Dizziness, drowsiness, hallucination, euphoria, LOC, pupil reaction
 Allergic reaction: Rash, urticaria
 Respiratory dysfunction:
Respiratory depression: Notify physician if respirations are > 12 / min
 Euphoria,
 Nausea,
 Vomiting

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PROMETHAZINE (PHENERGAN)
Promethazine is an antihistamine, H1- receptor antagonist belonging to the phenothiazine group.
Mechanism of Action
 Decreases allergic response by blocking histamine, sedative and antiemetic.
Indications
 Treatment of vomiting in pregnancy
 Sedation during labor
 Pregnancy induced hypertension
 Combined with pethidine to prevent vomiting
 In Rh isoimmunization to decrease the production of antibodies
 Allergic reactions.
Contraindications
 Acute asthma attack
 Lower respiratory tract disease
Dosage and Route of Administration
 Tablets: 25-50 mg/TID
 Injection: 50 mg/ml solution/BD
Side Effects / Adverse Reactions
 Drowsiness
 Dizziness
 Poor Coordination
 Fatigue
 Anxiety
 Confusion
 Neuritis
 Parasthesia

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Nursing Considerations
Assess
 Urinary output: Be alert for urinary retention, frequency, dysuria, drug should be
discontinued if these occur.
Administer
 Coffee, tea and cola (caffeine) to decrease drowsiness.
 With meals if GI symptoms occur when given orally.
 Deep IM in large muscle; rotate site.
Perform / Provide
 Hard candy or gum, frequent rinsing of mouth for dryness.
 Storage in light resistant container.
Evaluate
 Therapeutic response
 Respiratory status: Wheezing, chest tightness.
 Cardiac status: Palpitation, hypotension, increased pulse.
Teach Patient / Family
 That drug may cause photosensitivity, to avoid prolonged sunlight.
 To notify physician if confusion or hypo tension occurs.
 To avoid concurrent use of alcohol or other CNS depressants.
 To avoid drinking or other hazardous activity, if drowsiness occurs.
COAGULANT
VITAMIN K (PHYTONADIONE)
Vitamin K has not been reported to cause birth defects or other problems. However, the use
of vitamin K supplements during pregnancy is not recommended because it has been reported to
cause jaundice and other problems in the fetus.

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Mechanism of Action
 It promotes the hepatic formation of the clotting factors II, VII, IX and X.
Indications
 It is used to treat or prevent certain bleeding problems
 It helps liver to produce blood clotting factors
Contraindications
 Hypersensitivity
Adverse effects
 Pain and edema may occur at injection site
 Allergic reaction such as rash and urticarial may occur
 Hyperbilirubinemia
Dosage and routes of administration
 0.5mg IM within 1 hour of birth.
Nursing considerations
 Document the giving of the medication newborn to prevent an accidental doubling
 Observe for bleeding usually occurs on 2nd and 3rd day
 Observe for jaundice
 Observe for local inflammation.

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INTRODUCTION:
The term ' placental barrier ' is a contradiction as many drugs cross the barrier with the exception
of large organic ions such as heparin and insulin.
DEFINITION:
 Teratogenesis refers to the production of defects in the fetus.
 Teratogen usually is cited in the context of causing anatomical defects in an embryo that
was previously differentiating normally.
 Teratogenic drugs: A teratogen is an agent that can disturb the development of the
embryo or fetus. Teratogens halt the pregnancy or produce a congenital malformation (a
birth defect). Classes of teratogens include radiation, maternal infections, chemicals,
and drugs.
INCIDENCE:
 Approximately 25 % of human development defects are genetic in origin.
 2-3% is due to drug exposure.
 65 % are either unknown or from combination of genetic and environmental factors.
MECHANISM OF TERATOGENECITY:
The actual mechanism is unknown. Teratogens may affect through the following ways:
 Folate deficiency: Leads to deficient methionine production and RNA, DNA synthesis.
Periconceptional folic acid deficiency leads to neural tube defects, cleft lips and palate.
 Epoxides or arena oxides: are the oxidative inter metabolites of many drugs like
hydantoin and carbamazepine. These intermediary metabolites have carcinogenic and
teratogenic effects unless they are detoxified by fetal epoxide hydrolase.
TERATOLOGY IN PREGNANCY

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 Environment and Genes: Abnormalities that are multi factorial depends on the ultimate
interaction between the environment and fetal gene mutation. Homozygous gene
mutations are associated with more anomalies.
 Maternal disease and drugs (epilepsy and anticonvulsants) have an increased risk of
fetal anomalies. Paternal exposure to drugs or mutagens (polycyclic hydrocarbons) can
cause gene mutation and chromosomal abnormality in sperm.
 Homeobox genes are groups of regulatory genes that control the expression of other
genes involved in the normal development of growth and differentiation. Teratogens like
retinoic acid can activate these genes to cause abnormal gene expression.
MATERNAL-FETAL DRUG TRANSFER AND THE HAZARDS:
 Before D 31: Teratogen produces an all or none effect. The conceptus either does not
survive or survives without anomalies. In early conception only few cells are there.
So any damage at that phase, is irrepairable and is lethal.
 D 31 - D 71: It is the critical period for organ formation. Effects of teratogen depend
on the following factors:
 Amount of the drug reaching the fetus.
 Gestational age at the time of exposure.
 Duration of exposure.
 After D 71: Development of other organs continues. Last menstral period Diethyl
stilboesterol (DES) related uterine anomalies occur with exposure around 20 weeks.
Brain continues to develop throughout pregnancy and neonatal period. Fetal alcohol
syndrome occurs in late pregnancy.
 Placental transfer of drugs: Most drugs cross the placental barrier by simple diffusion.
The factors responsible for transfer are
 Molecular weight (molecular weight > 1000 Da do not Brain cross the placenta)
 Concentration of free drug.
 Lipid solubility

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 Utero placental blood flow
 Placental surface area.
The rate of drug transfer across the placenta is increased in late pregnancy.
FDA PREGNANCY CATEGORIES
CATEGORY A:
 Failed to demonstrate e a risk to the fetus in the first trimester of pregnancy.
 No evidence of risk in later trimesters.
CATEGORY B:
 Failed to demonstrate a risk to the fetus no adequate and well controlled studies in
pregnant women.
CATEGORY C
 Shown an adverse effect on the fetus.
 No adequate and well controlled studies in humans potential benefits may warrant the use
of drug despite potential risks.
CATEGORY D
 Positive evidence of human fetal risk based on adverse reaction data
 Potential benefits may warrant use of the drug in pregnant women despite potential risks.
CATEGORY X
 Demonstrates fetal abnormalities.
 Positive evidence of human fetal risk based on adverse reaction data.
 The risks involved in use of the drug in pregnant women.
Maternal medication Fetal or neonatal affection and comment
Cytotoxic drugs  Multiple fetal malformations
 abortion
Diethyl stilboestrol  Vaginal adenosis,
 Cervical hoods uterine hypoplasia of the

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female offspring.
Androgenic steroids  Masculinization of the female offspring
Lithium
 Cardiovascular ( Ebstein's ) anomalies
 Neonatal goitre
 Hypotonia
 Cyanosis
Phenytoin
(Anticonvulsants)
 Outweigh the risks to the fetus
 Cleft lip/Cleft palate
 Mental Retardation
 Limb defect & hypoplasia
Sodium valproate
(Anticonvulsants)
 Neural tube defect
 Neonatal bleeding
Anticoagulants
 Fetal wafarin syndrome : -
Nasal hypoplasia
Bone stippling
Bilateral optic atrophy
Mental retardation
 Respiratory distress syndrome
 Fetal and maternal hemorrhage
Analgesic (Aspirin)
 Gastroschisis
 Decrease prostaglandin
 Decrease uterine contraction
 Premature closure of ductus arteriosis,
 Persistent pulmonary hypertension
 Kernicterus in newborn
Antidepressant
(Imipramine )
 Cleft palate
 Defect in abdomen
 Adrenal hypoplasia
 Cardiovascular defect
Antithyroid
(Propylthiouracil &
Methimazole)
 Fetal goiter

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Vitamin K  Hyperbilirubinaemia
 Kernicterus
Sedative / Hypnotics
(Diazepam)
 Cleft lip and palate
 Inguinal hernia
 Congenital heart disease
 Pyloric stenosis
 Breathing difficulties
Aminoglycosides
(Streptomycin &
Canamycin)
 Auditory or vestibular damage.
Narcotics
 Depression of CNS
 Apnoea
 Bradycardia
 Hypothermia
Anaesthetic agents
 Convulsion
 Bradycardia
 Acidosis
 Hypoxia
 hypertonia
Corticosteroids
 High dose (> 10 mg prednisolone daily) may
produce fetal and neonatal adrenal
suppression
Oral contraceptives
 Arterial or venous thrombosis
 Severe hypertension
 Hyperlipidaemia
 Bronchial asthma

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Emergency Medications for the Neonates
Safe and timely administration of emergency medications and infusions is crucial when caring
for critically ill neonates. A neonatal emergency medication sheet can enhance preparation,
calculation, and administration of medications during emergency situations in neonatal intensive
care units (NICUs).
Medication Indication Dosage Side-effects
Furosemide Volume overload,
pulmonary edema
1 mg/kg/dose, IM, IV
Vasopressin 0.5 units/Kg IV/IO
Max dose: 40 units
Lorazepam Anticonvulsant 0.05 mg/kg/dose IV, infuse
over 3–5 minutes
May cause respiratory
depression and
hypotension, may
repeat in 10–15
minutes
Naloxone Narcotic reversal 0.1 mg/kg IM/IV (IV
preferred; IM acceptable
but delayed onset of
action). ETT route: no
studies in neonates
Not recommended as
part of initial
resuscitation of
newborns with
respiratory depression
in delivery room. If
respiratory depression
continues, naloxone
may be given if
mother had narcotics
within 4 hours of
delivery.
Phenobarbital Anticonvulsant 15–20 mg/kg IV load over
15–30 minutes
Respiratory
depression possible if
diazepam used first.
Phenytoin Anticonvulsant 15–20 mg/kg IV load IV rate 0.5 mg/kg/min
maximum; mix only

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with NS.
Sodium bicarbonate Documented
metabolic acidosis
with adequate
ventilation,
hyperkalemia
1–2 mEq/kg IV over at
least 30 minutes or more
Use 0.5 mEq/mL;
infuse over 30 minutes
or more.
Volume Expansion
Normal saline (preferred)
or lactated Ringer’s
solution
Volume expansion 10 mL/kg IV over 5–10
minutes; may repeat
Check Hct and serum
glucose before and
after dose.
Atropine Bradycardia 0.01–0.03 mg/kg/dose IV,
IM, ETT; repeat every 10–
15 minutes
For ETT use, dilute
with NS.
Calcium gluconate (10%)
(100 mg/mL)
Hyperkalemia
Hypocalcemia
Ca gluconate 100–200
mg/kg slow IV over 10–30
minutes (1.0–2.0 mL/kg)
Infuse slowly; caution
with digitalized
patient; tissue necrosis
if extravasation. Can
also use CaCl 20–30
mg/kg.
Dextrose Hypoglycemia
Hyperkalemia
(used with insulin)
100–500 mg/kg/dose IV
(1–5 mL/kg/ dose D10W)
D10 = 100 mg/mL;
D12.5 = 125 mg/mL;
D25 = 250 mg/mL
(D25 only in central
line).
Dobutamine Cardiogenic shock,
hypotension due to
refractory CHF
2–15 mcg/kg/min, increase
every 10 minutes to
maximum 40 mcg/kg/min
Mix in D5W, NS, LR.
Dopamine Hypotension,
agonal heart
5 mcg/kg/min, increase to a
maximum of 40
mcg/kg/min
Mix in D5W, NS, LR.
Epinephrine (1:10,000) Asystole,
bradycardia,
hypotension (acute)
0.1–0.3 mL/kg/dose of
1:10,000 IV; ETT only 0.5–
1 mL/kg/dose of 1:10,000
(dilute with NS)
Do not use 1:1000; for
ETT use, dilute in 1–2
mL NS; NRP, AHA,
AAP suggests higher
dose if by ETT.

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REFERENCE:
 A comprehensive text book of Midwifery & Gynecology Nursing, Annamma Jacob,
Jaypee Publications, 3rd
Edition, Chapter: Drugs Used in Obstetrics, Page No. 604-616.
 DC Dutta's Textbook of Obstetrics, Author: D. C. Dutta, Editor: Hiralal Konar, Publisher:
Jaypee Brothers Medical Publishers.
 https://www.slideshare.net/deepthyphilipthomas/pharmacotherapeutics-in-obstetrics
 https://uichildrens.org/health-library/emergency-drugs-picu-chart
 https://accesspediatrics.mhmedical.com/content.aspx?bookid=1303&sectionid=79657427
 https://www.slideshare.net/syeimy/teratogenic-drugs