endocrine medications

1. Endocrine drugs
Chapter 8

2. Endocrine drugs
 Hypothalamic & pituitary hormones
 Antidiabetic drugs
 Drugs for thyroid disorders
 Adrenocorticosteroids & adrenocortical
antagonists
 The gonadal hormones & inhibitors
 A gents that affect bone mineral homeostasis
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3. Endocrine drugs
I. Antidiabetic Drugs
3

4. Overview of DM
 DM is not a single disease entity but rather a
group of metabolic disorders sharing the common
underlying feature of hyperglycemia
 Hyperglycemia in DM results from
 Defects in insulin secretion, insulin action, or,
most commonly, both
 It affects more than 120 million people world-wide
 It is estimated that it will affect 220 million by
the yr 2020
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5. Overview of DM …
 Type 1 DM
 An autoimmune disease in which islet
destruction is caused primarily by
• T lymphocytes reacting against as yet poorly
defined β-cell antigens, resulting in a
reduction in β-cell mass
 Genetic susceptibility & environmental influences
play important roles in the pathogenesis
 Most commonly develops in childhood, becomes
manifest at puberty & progressive with age
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6. Overview of DM …
 Type 2 DM
 Like Type 1 DM, the pathogenesis of type 2 DM
remains enigmatic
 Environmental influences, such as a sedentary
life style & dietary habits have a role
 Genetic factors are more important than in type 1
DM
 The 2 metabolic defects that characterize type 2
DM
• Insulin resistance
• ↓ed ability of peripheral tissues to respond to insulin
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7. Overview of DM…
 β-cell dysfunction
• Manifested as inadequate insulin secretion in
the face of insulin resistance & hyperglycemia
NB: In most cases, insulin resistance is the 10
event
& followed by ↑sing degrees of β-cell dysfunction
 Type 3 DM
 The type 3 designation refers to multiple other
specific causes of an elevated blood glucose:
pancreatectomy, pancreatitis, non-pancreatic
diseases, drug therapy, etc
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8. Overview of DM…
 Type 4 DM
 Gestational diabetes (GDM) is defined as any
abnormality in glucose levels noted for the 1st
time
during pregnancy
 During pregnancy, the placenta & placental hormones
create an insulin resistance that is most pronounced in
the last trimester
 Risk assessment for DM is suggested starting at the 1st
prenatal visit
 High-risk women should be screened immediately
 Screening may be deferred in lower-risk women until the
24th to 28th wk of gestation
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What are therisksfactorsassociatedwith
GDM?
• Althoughany womancan develop GDMduringpregnancy,
someof thefactors thatmay↑the riskinclude thefollowing:
• Overweightor obesity
• Family history of DM
• Havinggivenbirth previously to avery largeinfant,astill
birth,ora childwitha birthdefect
• Age (women who are older than25areata greater risk for
developing GDM than youngerwomen)
• Race (womenwho areAfrican-American,American Indian,
AsianAmerican,Hispanic/Latino, or PacificIslander havea
higher risk)
• Prediabetes

9. Types of Antidiabetic Agents
A. Injectable antidiabetic agents: Insulins
B. Oral antidiabetic agents
Both aim to produce normal blood glucose states
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10. A. Insulin preparations:
 Role of Insulin
 The actions of insulin on cells include:
• Increased glycogen synthesis
• Increased fatty acid synthesis
• Increased esterification of fatty acids
• Decreased proteinolysis
• Decreased lipolysis
• Decreased gluconeogenesis
• Increased amino acid uptake
• Increased potassium uptake
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11. Insulin preparations
 4 principal types of injected insulins are available:
 Rapid-acting→ very fast onset & short duration
 Short-acting → rapid onset of action
 Intermediate-acting →slow onset of action
 Long-acting: → slow onset of action
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12. Insulin preparations …
 Rapid acting
 Most rapid onset of action (5-15 min)
 Shorter duration
• Insulin aspart, Insulin lispro
 Short acting
 Regular insulin
 The only insulin product that can be given by IV bolus,
IV infusion, or even IM
 NB: Injected rapid acting & short-acting insulins are
dispensed as clear solutions at neutral pH & contain small
amts of zinc to improve their stability and shelf life
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13. Insulin preparations …
 Intermediate acting
 Isophane insulin suspension (also called NPH)
 Insulin zinc suspension (also called Lente)
 Both have a cloudy appearance
 Slower in onset & more prolonged duration than
endogenous insulin
 Long acting
 Glargine: Clear, colorless solution
 Extended insulin Zn suspension (Ultralente)
• White, opaque solution
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14. Insulin preparations …
 Combination Insulin products
 NPH 70% & regular insulin 30% (70/30)
 NPH 50% & regular insulin 50% (50/50)
 Insulin lispro protamine susp 75% & insulin
lispro 25% (75/25)
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15. 15
PK of most commonly used insulin preparations
Insulin type Onset of
action
Peak effect Duration
of action
pH
Lispro, aspart,
glulisine
5 - 15 min 45 - 75 min 2 - 4 h 6.9 - 7.8
R-insulin About 30 min 2 - 4 h 5 - 8 h 6.9 - 7.8
NPH About 2 h 4 - 12 h 18 - 28 h
Insulin
glargine
About 2 h No peak 20 - >24 h 4
Insulin detemir About 2 h 3 - 9 h 6 - 24 h*
NPL About 2 h 6 h 15 h
* Duration of action is dose-dependent. At higher doses (≥0.8 units/kg), mean
duration of action is longer & less variable (22 -23 hrs).

16. Insulin preparations …
 Complications of insulin therapy
 Hypoglycemia (“hypo” “insulin rxn”)
• Most common adverse effect of insulin
• Timing of hypoglycemia differs among various insulin
formulations
• Hypoglycemia may result from
• Late meal, too little CHO, extra exercise, too
much insulin
 Weight gain
 Local lipodystrophy (lipohypertrophy or
lipoatrophy)
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Fig. lipoatrophy
Fig: Abdomen siteof injection showing
hypertrophyand scars

17. B. Oral Antidiabetic Agents
 Used for type 2 DM
 Tx for type 2 DM includes lifestyle modifications
 Diet, exercise, smoking cessation, wt loss
 Oral antidiabetic agents may not be effective
unless the pt also makes behavioral or lifestyle
changes
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18. a) Sulfonylureas
 Drugs includes: glibenclamide, glipizide, glimepride
 Stimulate release of insulin from pancreas to lower
blood glucose
 Must have functioning pancreatic beta cells
 Side effects: Hypoglycemia, N, skin reactions
(including photosensitivity), & abnormal liver
function tests, Wt gain
 Administer 30 minutes before meals
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Fig. One model of control of insulin release from the pancreatic beta
cell by glucose and by sulfonyl urea drugs

19. b) Biguanide: metformin
 Increases use of glucose by muscle & fat cells
 Decreases hepatic glucose production
 Decreases intestinal absorption of glucose
 Most common SEs of metformin are GI, including
 A metallic taste in the mouth, mild anorexia, N, D,
abdominal discomfort
 Lactic acidosis is an uncommon SE
 C/I in serious hepatic or renal impairment or other
conditions that may ↑ lactate production- potentially
fatal lactic acidosis
 Administer with meals
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– In pts with renal disease, alcoholism, hepatic
disease, or
– Conditions predisposing to tissue anoxia (eg,
chronic cardiopulmonary dysfunction)
– b/c of the increased risk of lactic acidosis
induced by this drug
Metformin is C/I:

20. c) Meglitinides
 Includes: Repaglinide & nateglinide
 Similar action to sulfonylureas- stimulate
pancreatic secretion of insulin
 Short-acting glucose-lowering drugs given alone or
in combination with metformin
 Efficacy when taken just 15 minutes before meals
 A duration of effect of no more than 3 hrs
 Similar risk for wt gain as sulfonylureas but
possibly less risk of hypoglycemia
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21. d) Glitazones (Thiazolidinediones)
 Includes: Rosiglitazone, pioglitazone
 Reduce insulin resistance in the tissues
 ↑ insulin sensitivity by acting on adipose, Ms, &
liver to ↑glucose utilization & ↓ glucose production
 Use cautiously in pts with CHF: ↑ plasma volume &
may cause fluid retention
 Administer with meals
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22. e) Alpha-Glucosidase Inhibitors
 Includes: Acarbose, Miglitol
 Inhibit digestive enzymes in GIT (such as sucrase,
maltase, amylase) responsible for release of glucose
from consumed CHO, so absorption is delayed
 C/I in inflammatory or malabsorptive intestinal
disorders
 Administer just before meals
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23. Antidiabetic Agents: Nursing
Implications
 Before giving any drugs that alter glucose levels,
obtain & document:
 A thorough history
 Vital signs
 Blood glucose level
 Potential complications & drug interactions
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24. Nursing Implications…
 Before giving any drugs that alter glucose levels:
 Assess the pt’s ability to consume food
 Assess for N or V
 Hypoglycemia may be a problem if antidiabetic
agents are given & the pt does not eat
 If a pt is NPO for a test or procedure, consult
physician to clarify orders for antidiabetic drug
therapy
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25. Nursing Implications…
 Keep in mind that overall concerns for any diabetic
pt ↑when the pt:
 Is under stress
 Has an infection
 Has an illness or trauma
 Is pregnant
 Thorough pt education is essential regarding:
 Disease process
 Diet & exercise recommendations
 Self-administration of insulin or oral agents
 Potential complications
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26. Nursing Implications…
 When insulin is ordered, ensure:
 Correct route
 Correct type of insulin
 Timing of the dose
 Correct dosage
 Insulin order & prepared dosages are second-
checked with another nurse
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27. Nursing Implications…
 Insulin
 Check blood glucose level before giving insulin
 Roll vials b/n hands instead of shaking them to mix susp
 Ensure correct storage of insulin vials
 ONLY insulin syringes, calibrated in units, are to be used to
measure & give insulin
 Ensure correct timing of insulin dose with meals
 When drawing up 2 types of insulin in one syringe, always
withdraw the regular insulin first
 Provide thorough pt education regarding self-administration of
insulin injections, including timing of doses, monitoring blood
glucoses, & injection site rotations
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28. Nursing Implications…
 Oral antidiabetic agents
 Always check blood glucose levels before giving
 Usually given 30 minutes before meals
 Alpha-glucosidase inhibitors are given with the
first bite of each main meal
 Metformin is taken with meals to reduce GI effects
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29. Nursing Implications…
 Assess for signs of hypoglycemia
 If hypoglycemia occurs:
 Give glucagon
 Have the pt eat glucose tabs or gel, corn syrup,
honey, fruit juice or non-diet soft drink
 Or have the pt eat a small snack such as
crackers or half a sandwich
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30. Nursing Implications…
 Monitor blood glucose levels
 Monitor for therapeutic response
 ↓ in blood glucose levels to the level
prescribed by physician
 Watch for hypoglycemia & hyperglycemia
 Measure hemoglobin A1c to monitor long-term
compliance to diet & drug therapy
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31. Endocrine drugs…
II. Drugs for thyroid disorders

32. Overview
 The thyroid gland is located in the neck in front of
the trachea
 This highly vascular gland manufactures &
secretes 2 hormones: thyroxine (T4) &
triiodothyronine (T3)
 Iodine is an essential element for the manufacture
of both of these hormones
 The activity of the thyroid gland is regulated by
thyroid-stimulating hormone, produced by the
anterior pituitary gland
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33. Overview
 Two diseases are related to the hormone-producing
activity of the thyroid gland:
 Hypothyroidism—a decrease in the amt of
thyroid hormones manufactured & secreted
 Hyperthyroidism—an ↑ in the amt of thyroid
hormones manufactured & secreted
• A severe form of hyperthyroidism, called
thyrotoxicosis or thyroid storm, is
characterized by high fever, extreme
tachycardia, & altered mental status
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34. A. Drugs for Hypothyroidism
 Thyroid hormone influences many systems &
processes in the body, including the following:
 Metabolic: energy levels, body temp, wt, lipids,
appetite
 CV: HR, heart rhythm, BP, fluid distribution
 Skin & hair: composition, thickness, texture
 GI: motility
 Musculoskeletal: bone growth, tendon reflexes
 Hematologic: erythropoiesis
 Reproductive: ovulation & spermatogenesis
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35. Drugs for Hypothyroidism…
 Thyroid hormone preparations include:
 Levothyroxine Na
 Others: Liothyronine, liotrix, thyroid (desiccated)
 Levothyroxine Na
 Dosage Forms: Tabs, injection
 Indication: Hypothyroidism from any cause
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36. Drugs for Hypothyroidism…
 Levothyroxine Na…
 Adverse reactions: most common
• Fatigue, ↑ed appetite, wt loss, heat intolerance,
hyperhidrosis
 Adverse reactions: rare/severe/important
• Hair loss, menstrual irregularities, nervousness,
irritability, insomnia
 C/Is:
• Caution must be exercised in conditions in which
tachycardia is dangerous (CAD, aortic stenosis,
mitral stenosis)
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37. Drugs for Hypothyroidism…
 Levothyroxine Na: Nursing considerations
 The Tx is initiated slowly (with small doses) &
gradually increased
 Store medications in cool dark place
 Take complete nursing history
 Note if the client is taking antidiabetic drugs &
document
 Take baseline ECG. then at regular intervals
 Monitor thyroid function closely
 Observe client for side effects
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38. Drugs for Hypothyroidism…
 Levothyroxine Na: Nursing considerations…
 Monitor PT & PTT closely since the drug ↑
hypoprothrombinemia
 Monitor HR & BP closely for cardiac pts
 Instruct the client to report SEs e.g. wt loss &
nervousness to physician
 Have dietitian counsel clients regarding diet
according to the energy demands
 Female client should record menstrual irregularities
 Encourage the client to keep follow-up visits
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39. B. Drugs for Hyperthyroidism
 Drugs for Hyperthyroidism
 Thionamides: propylthiouracil (PTU) &
methimazole
 Radioactive Iodine (131
I)
 Nonradioactive Iodine: Strong Iodine Solution
(Lugol's Solution), Na Iodide (IV), K Iodide
 Beta blockers
• can suppress tachycardia & other symptoms
of Hyperthyroidism
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40. Drugs for Hyperthyroidism...
1. Thionamides: propylthiouracil (PTU)
 Act primarily by blocking the synthesis of thyroid
hormone
 Require about 3 to 12 wks to exert their effects b/c
of the thyroid precursors of thyroid synthesis that are
stored inside the thyroid gland
 Adverse Effects:
• The most common (in 6% to 10% of pts) are skin rash,
fever, & arthralgia (sore joints)
• Serious, Rare Side Effects : Agranulocytosis,
Hepatotoxicity, Vasculitis
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41. Drugs for Hyperthyroidism...
 PTU has 4 therapeutic applications in
hyperthyroidism:
 Reduction of thyroid hormone production in
Graves' disease
 Control of hyperthyroidism until the effects of
radiation on the thyroid become manifest
 Suppression of thyroid hormone production prior
to subtotal thyroidectomy
 Treatment of thyrotoxic crisis
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42. Drugs for Hyperthyroidism...
 PTU: Nursing implication
 Obtain serum levels of free T3 & free T4 as a
baseline data
 Use with caution during pregnancy & lactation
 Instruct the pt to take PTU at regular intervals
around-the-clock (usually every 8 hrs)
 Evaluate Tx by monitoring for wt gain, ↓ed HR, &
other indications that levels of thyroid hormone have
declined
 Inform pts about early signs of agranulocytosis
(fever, sore throat), & instruct them to notify the
physician if these develop
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43. Drugs for Hyperthyroidism...
2. Radioactive iodine (131
I)
 Destroys the thyroid gland via radiation
 Indications: Hyperthyroidism, Thyroid cancer
 Adverse effects:
• Hypothyroidism: Almost all pts require lifelong thyroid
replacement after radioactive ablation
• Sialadenitis: Inflammation of the salivary glands
occurs b/c of uptake of 131
I
• Salivary damage can result in xerostomia (dry
mouth), altered taste, ↑ed dental caries, & pain
• Cancer: Although very small, a risk of cancer arises
from the radiation from the 131
I
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44. Drugs for Hyperthyroidism...
 C/Is:
 Absolutely C/I in pregnancy pregnancy &
lactation
• Furthermore, pregnancy must be avoided for
6 months following administration of 131
I
 Relatively contraindicated in children: There is a
small risk of cancer
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45. Drugs for Hyperthyroidism...
3. Strong iodine solution (lugol's solution)
 Therapeutic Goal:
• Suppression of thyroid hormone production
in preparation for subtotal thyroidectomy
• Also used to suppress thyroid hormone
release in pts experiencing thyroid storm
 Baseline Data: Obtain tests of thyroid function
 Administration:
• Advise pts to dilute strong iodine solution with
fruit juice or some other beverage to increase
palatability
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46. Drugs for Hyperthyroidism...
 Mild Toxicity
 Inform pts about Sx of iodism (brassy taste, burning
sensations in the mouth, soreness of gums & teeth), &
instruct them to discontinue Tx & notify the prescriber if
these occur
 Symptoms fade upon drug withdrawal
 Severe Toxicity
 Iodine solution can cause corrosive injury to the GIT
 Instruct pts to discontinue the drug & notify the prescriber
immediately if severe abdominal distress develops
 Tx includes gastric lavage & giving Na thiosulfate
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