2. Chapter One
Terms and Definitions
Scope of Subjects
Sources of Drugs
Routes of Drug administration
Drug standards and Pharmacopoeia
Pharmacology Textbooks
Drug nomenclature
Drug classifications
Drug development
3. Pharmacological Textbooks
Goodman and Gilman's the Pharmacological
Basis of Therapeutics, 12th ed.
Principles of Medical Pharmacology
Pharmacology: Principles and Practice
Modern Pharmacology with Clinical applications
4. Veterinary pharmacology books
Veterinary Pharmacology and Therapeutics. 9th
ed
Small animal clinical pharmacology and
therapeutics, 2nded by Boothe
Small animal clinical pharmacology, 2nded by
Maddison
13. Definitions
Def1: Pharmacology is the study of drugs.
Def2: Pharmacology is the study of pharmacokinetic
and pharmacodynamic studies of drugs.
Def3: Pharmacology is a scientific discipline that studies
about chemical, therapeutic and the side effects of
drugs.
14. What is a Drug?
In WHO drug is defined, any substance or product
that is used to explore a physiological systems or
pathological states for the benefit of the recipient.
Word of drug derived from French word, drogue
meaning dry herb which is used for diagnosis,
prevention and cure of a disease.
Dose, it is the quantity of the drug.
Dosage, it is the schedule of the dose, frequency and
duration of administration of drugs.
15. Sources of Drugs
Drugs are obtained from different sources. They are
natural and synthetic.
1. plants: atropine from atropa belladona, digoxin from
digitalis purpura, morphine from papavarum
somniferum, quinine from cinchona bark.
2. Animals: insulin, heparin and gonadotropin
3. Minerals: magnesiun sulphate, iron, lithium.
16. Continued
4. Microorganisms: penicillins from penicillium
chrysogenum, cephalosporins.
5. Human sources: growth hormone, insulin, chorionic
gonadotropins from pregnancy ladys urine.
18. Drug dosage
Dose is the appropriate amount of a drug needed to
produce a certain degree of response in a patient.
Dose can be classified into:
1. Standard dose e.g contraceptives , chloroquine
2. Regulated dose e.g anticoagulants, diuretics
3. Target level dose e.g digoxin, lithium
4. Titrated dose e.g anticancer drugs & levodopa
20. Pharmacokinetics
Pharmacokinetic is the study of what actually happens
to a drug from the time it is put into the body until the
time all of it and it is metabolites have left the body.
Pharmacokinetic is what body do to the drug.
Pharmacokinetic is the study of absorption,
distribution, metabolism and excretion (ADME).
21. Absorption
• Drug absorption is the processes of incorporating a drug
into the body and its various tissues, organs and other
biological sites.
• If two medications have the same bioavailability, they are
said to be bio-equivalent.
• Bioavailability is the amount of a drug in a particular
dosage form that is absorbed into the circulation.
• There are various factors that affecting the rate of drug
absorption, these include administration route of a drug,
food, and fluids, administered with a drug, the dosage
formulation, the status of the absorptive surface, and the
acidity of the stomach.
22. Distribution
Once a drug enters the blood stream (circulation), it is
distributed throughout the body.
A drug can be freely distributed to extravascular tissue
only if it is not bound to a protein. If a drug is bound
in to a protein, it is generally too large to pass into
tissues.
The transport of a drug that in the body by the blood
stream to its site of action is referred to us distribution.
23. Continue
There are three primary proteins that carry that bind
to and carry drugs throughout the body and they are:
Albumin (most important)
Alpha 1 acid glycoprotein
Corticosteroid binding globulin
Distribution can be classified into two compartments:
Rapid distribution like heart, liver, kidney and brain.
Slow distribution like muscle, skin and fat
24. continue
A theoretical volume, called volume of distribution,
is sometimes used to describe the various areas where
drugs may be distributed.
Typically a drug that is highly water soluble will have a
small volume of distribution and high blood
concentrations.
Fat soluble drugs have a large volume of distribution
and low blood concentrations.
25. Metabolism
Metabolism is also referred to as biotransformation
because it involves the biologic transformation of a
drug into an inactive metabolite, a more soluble
compound or a more potent metabolite.
Biotransformation is the next step after absorption and
distribution.
The organ most responsible for the biotransformation
or metabolism of drugs is the liver. Other tissues and
organs that aid in the metabolism of drugs are the
kidney, lungs, plasma, and intestinal mucosa.
26. Continue
Biotransformation means chemical alteration of the
drug in the body.
The biotransformation capabilities of the liver can vary
considerably from patient to patient.
Hepatic biotransformation involves the use of an
enormous variety of microsomal enzymes.
27. Assignment
Biotransformation reactions can be classified into:
1. non-synthetic or phase I reactions: like oxidation,
reduction, hydrolysis, cyclization, and decyclization.
2. Synthetic reactions: like glucuronide conjugation,
acetylation, methylation, sulfate conjugation,
Glycine conjugation, glutathione conjugation.
28. Excretion
The elimination of drugs from the body is referred to
as excretion.
The primary organ that is responsible for excretion is
kidney.
Two other organs that also play an important role in
the excretion of drugs are the liver and the bowel.
The actual act of excretion is accomplished through
glomerular filtration, resorption, and tubular
29. Continue
Excretion is the passage out of systemically absorbed
drug.
The excretion of drugs by the intestines is another
common route of elimination. This is also referred to
as biliary excretion. Drugs that are eliminated by this
route are taken up by the liver, released into the bile,
and eliminated in the feces.
30. Half life
It is the time it takes for one half of the original
amount of a drug in the body to be removed and is a
measure of the rate at which drugs are removed from
the body.
E.g tetracycline 500mg, it is first half life is 250mg.
31. Half life of some representative
drugs
Aspirin 4 hours
Penicillin G 30 minutes
Doxycycline 20 hours
Digoxin 40 hours
Digitoxin 7 days
Phenobarbitone 90 hours
32. Onset, Peak, Duration
The terms onset, peak, and duration are used to
describe drug effects.
A drug onset of action is the time it takes for the
drug to elicit a therapeutic response.
The time it takes for a drug to reach it is maximum
therapeutic response is its peak effect.
The duration of action of a drug is the time that drug
concentration is sufficient to elicit a therapeutic
response.
33. Pharmacodynamic
The study of the mechanism of drug actions in living
tissues is called pharmacodynamics.
Pharmacodynamics is what drug does to the body.
Pharmacodynamics can be classified into:
Therapeutic utility
Mechanism of action
Receptor interactions
34. Principles of drug action
The principles of drug actions are as the following:
1. Stimulation
2. Depression
3. Irritation
4. Replacement
5. Cytotoxic actions
35. Stimulation
It refers to selective enhancement of the level of
activity of speacilized cells. e.g adrenaline stimulates
heart, pilocarpine stimulates salivary glands. However
excessive stimulation is often followed by depression
of that function, e.g picrotoxin a central nervous
system stimulant produces convulsions followed by
coma and respiratory depression.
36. Depression
It means selective diminution of activity of specialized
cells. E.g barbitutares depress CNS, quinidine
depresses heart. Certain drugs stimulate one type of
cells but depress the other. E,g acetylcholine
stimulates intestinal smooth muscle but depress
sinoatrial node in heart, thus most drugs cannot be
simply classed as stimulants or depressants.
37. Irritation
This connotes a nonselective often noxious effect and
is particularly applied to less speacilized cells. Mild
irritation may stimulate associated function. E.g
bitters increase salivary and gastric secretion,
counterirritants increase blood flow to the site, but
strong irritation results in inflammation, necrosis, and
morphological damage.
38. Replacement
This refers to the use of natural metabolites, hormones
or their congeners in deficiency states. E.g levodopa in
parkinsonian, iron in anemia, insulin in diabettes.
39. Cytotoxic action
Selective Cytotoxic action for invading parasites or
cancer cells, attenuating them with out significantly
affecting the host cells is utilized for cure of infections
and neoplasm's. E.g. zidovudine, chloroquine,
penicillin.
41. Combined effects of drugs
When two or more drugs are given simultaneously or
in quick succession, they may be either indifferent to
each other or exhibit synergism or antagonism.
The interaction may take place at pharmacokinetic
level or at pharmacodynamic level.
42. Synergism
When the action of one drug is facilitated or increased
by other, they are said to be synergistic. In synergistic
pair both the drugs can have action in the same
direction or given alone one may be inactive but still
enhance the action of the other when given together.
Synergism can be:
1. Additive
2. Supraadditive
43. additive
The effect of the two drugs is in the same direction and
simply adds up. E.g effect of drugs A+B= effect of drug
A + effect of drug B.
Examples are the following:
Aspirin + paracetamol = analgesic/antipyretic
Nitrous oxide + halothane = general anesthesia
Amlodipine + atenalol = antihypertensive
Glibenclamide + Metformin = hypoglycemic
Ephedrine + Theophylline = bronchodilator
44. Supraadditive
The effect of combination is greater than the
individual effects of the components.
Effect of drug A + B is greater than effect of drug A +
effect of drug B.
Examples are the following:
1. Acetylcholine plus physostigmine
2. Levodopa plus carbidopa plus benserazide
3. Adrenaline plus cocaine plus desipramine
4. Sulfamethaxazole plus trimethoprim
5. Enalapril plus hydrochlorothiazide
45. Antagonism
When one drug decreases or abolishes the action of
another, they are said to be antagonistic.
Effect of drug A + B is less than effect of drug A + effect
of drug B.
Antagonism can be classified into:
1. Physical antagonism e.g charcoal adsorbs alkaloids
2. Chemical antagonism e.g heparin intercts penicillin
3. Physiological antagonism e.g glucagon & insulin
4. Receptor antagonism e.g agonist & antagonist drugs
47. Pharmacotherapeutics
Pharmacotherapy is a dynamic process that should be
occurring continuously throughout a patient’s therapy.
The use of a medication to treat a pathologic
condition is called Pharmacotherapeutics.
48. Acute Therapy
Acute therapy involves intensive drug therapy and is
typically implemented in the critically ill patient. It is
generally needed to sustain life. Examples are the
administration of vasopressors to maintain blood
pressure and cardiac output after open heart surgery or
the use of volume expanders in a patient who is in
shock.
49. Maintenance Therapy
Maintenance therapy typically does not eradicate the
problems the patient may have but doesn’t prevent
progression of the disease. It is used for the treatment
of chronic illnesses such as hypertension.
The drug therapy maintains the patient’s blood
pressure within certain limits, which prevents certain
end organ damage.
50. Supplemental Therapy
Supplemental or replacement therapy supplies the
body with a substance needed to maintain normal
function.
This substance may be needed either because it cannot
be made or because it is deficient in quantity.
Examples are the administration of insulin to diabetic
patients or iron to patients with iron deficiency
anemia.
51. Palliative Therapy
The goal of palliative therapy is to make the patient as
comfortable as possible. It is typically used in the end
stages of an illness when all possible therapy has
failed.
The use of high dose narcotic analgesics to relieve pain
in the final stages of cancer is an example; the use of
oxygen in end stage of pulmonary disease is another.
52. Supportive Therapy
Supportive therapy maintains the integrity of the body
functions while the patient is recovering. Providing
fluids and electrolytes to prevent dehydration in a
patient with the flu who is vomiting and has a diarrhea
is an example.
Giving fluids, volume expanders or blood products to a
patient who has lost blood during surgery is an
example.
53. Prophylactic Therapy
Prophylactic therapy is drug therapy provided on the
basis of prior practical experience. It is based on
scientific knowledge often acquired during years of
observation of a disease and it is causes.
57. Drug Classification
Drugs are classified by:
1. Chemistry, e.g electrolytes
2. Mechanism, e.g beta-blockers and benzodiazepines.
3. Disease, e.g anti-hypertensive and anti-emetics
58. Classification of drugs by legal
purposes
Drugs are grouped for legal purposes as follows:
1. Official drugs: drugs which are included in the
pharmacopeias of that particular country are termed
official drugs.
2. Dangerous drugs: this include drugs of addiction. E.g
opium and cannabis.
3. Prescription drugs (POM): drugs which are given
only by the prescription of the doctor.
4. Over the counter (OTC): drugs which are available by
public with out prescription.
59. Pharmacopoeias
Book containing directions for the identification of
samples and the preparation of compound medicines,
and published by the authority of a government or a
medical or pharmaceutical society
A reference work for pharmaceutical drug
specifications.
61. Pharmacopoeia
1. IP: Indian pharmacopoeia
2. BP: British Pharmacopoeia
3. USP: United states Pharmacopoeia
4. P.P: Pakistan Pharmacopoeia
5. C.P: China Pharmacopoeia
62. Drug Nomenclature
A drug generally has three categories of names:
1. Chemical name
2. Non-proprietary name
3. Proprietary name
63. Chemical name
It describes the substance chemically,. E.g 1-
isopropylamino-3-1-naphthyloxy propan 2-ol.
This is cumbersome and not suitable for use in
prescribing.
64. Non-proprietary name
It is the name accepted by a competent scientific
body/authority, e.g united states adopted name
(USAN) by the council of USAN council.
Similarly, there is the British approved name (BAN) of
a drug. The non proprietary names of newer drugs are
kept uniform by an agreement to use the
recommended international non proprietary name
(rINN) in all member countries of W.H.O.
65. Proprietary (Brand) name
It is the name assigned by the manufacturers and is
his property or trade mark.
One drug may have multiple proprietary names.
Example: altol, atcardil, atecor, aten, betacard, lonol,
tenormin, tenalol for atenalol from different
manufactures.
Brand names are designed to be catchy, short, easy, to
remember.
66. Adverse Drug Reactions
1. Side-effects. e.g Atropine: dry mouth
2. Toxic effects: mostly seen with higher doses. E.g
Morphine, respiratory depression.
3. Drug tolerance: single dose of streptomycin
producing vestibular dysfunction.
4. Idiosyncratic reactions: e.g barbiturates produce
CNS stimulation.
5. Allergic reactions: immunologically based adverse
reactions to drugs are called allergic reactions which
are not related to pharmacological actions of drugs.
67. Factors modifying the action of
drugs
1. Body weight, Clarks rule: dose: body weight in kg
times average adult dose divide by 70.
Example
A patient whose body weight is 65kg has been taken
paracetamol. If the average adult dose of paractemol
is 500mg. Calculate the dose of this patient.
Result: 464.3 mg
68. Continued
Body surface area (BSA): The individual dose = BSA
(m2) / 1.7 times average adult dose.
The BSA (m2)= BW(kg) 0.425 times Height (cm) 0.725
times 0.007184
Result: 677.1 mg
69. Continue
2. Age, Youngest rule: age in years times adult dose
divide by age in years plus 12.
Example
A patient whose his age is 11 years has been taken Aspirin
365mg. Calculate the dose of this patient.
Result: 174.56mg
Dillings Formula: child dose= Age times adult dose
divide by 20.
Result: 200.175mg
71. Continue
6. Route of administration. E.g Magnesium sulphate
7. Genetic factor. E.g G6PD patients causes
hemodialysis.
8. Diseases. E.g liver diseases
9. Renal dysfunction. E.g kidneys, streptomycin,
Amphotericin B, phenytoin.
10. Tolerance: can be grouped into natural and acquired.
72. Pregnancy considerations
Increased maternal heart rate, cardiac output and
blood volume.
Drugs may cross placenta
Drugs may cross into a breast milk
Teratogens
76. Continue
8. ss: One half
9. tbsp: Tablespoon
10. tsp: Teaspoon
11. ID: intradermal
12. IM: intramuscular
13. IV: intravenous
14. OD: right eye
15. OS: left eye
77. Continue
16. OU: both eyes
17. PO: by mouth
18. SC: subcutaneous
19. SL: sublingual
20: AA: of each
21: Ac: before meals
22. Ad lib: as desired
23. bid: Twice a day
78. Continue
24. h: hour
25. hs: hour of sleep
26. noct: night
27. pc: after meals
28. prn: when needed
29. qd: every day
30: qh: every hour
31: qid: four times a day
79. Continue
32. qod: every other day
33. sos: if necessary
34. stat: immediately
35. tid: three times a day
80. Essential Drug Concept
W.H.O has defined (essential drugs) as those drugs
which satisfy priority health needs of the population.
They are selected with due regard to public health
relevance evidence on efficacy, safety and comparative
cost effectiveness.
Should be available at all times and adequate amounts.
81. Routes of Drug Administration
Drugs may be administered by various routes:
1. Enteral
2. Parentral
3. Rectal
4. Topical
82. Enteral routes
Enteral means through gastrointestinal tract.
1. Oral route
It is the most common route of administration. GIT
has a large surface area and different PH at different
parts helps absorption of drugs. At the same time
some drugs can be destroyed by the enzymes
secreted in gastrointestinal tract.
83. Advantages
Convenient: patients can swallow them selves
Economical: oral compounds are cheaper.
Non-invasive : no technique is required, no syringes
and needles.
84. Disadvantages
Slow onset of action
Bitter drugs may cause irritation like nausea and
vomiting.
Some drugs are not absorbed. E.g streptomycin
Some are destroyed. E.g insulin
Cannot be given to unconcious and uncooperative
patients
Some drugs may undergo extensive first pass
metabolism.
86. Factors that affects oral route
Food interferes with absorption of some drugs.
Milk, calcium can affect
Drugs should be swallowed with lot of water and
sitting position.
88. Injections
1. intradermal: in intradermal injection the drug is
injected into the layers of skin. E.g BCG vaccine.
2. Sub-cutaneous: when the drug is injected below the
skin, it is absorbed slowly.
3. Intramuscular: is an injection in to the skeletal
muscles.
4. Intravenous: the drug is injected directly into the
vein.
89. Advantages & disadvantages IV
Advantages
1. In emergency
2. Unconscious patients
3. When the drug is not suitable for IM or
subcutaneous injections.
4. When large volumes are required. E.g NS, 5%
Dextrose
90. Continue
Disadvantage s
1. Rupture of vein
2. Transmission of diseases through blood transfusion
3. Should be given only to trained person
91. Inhalational Administration
Some drugs may be given by inhalation through nose
to produce either local action on the respiratory tract
or systemic action. They are absorbed through lungs.
E.g beclomethasone, salbutamol.
92. Transdermal Administration
Highly lipid soluble drugs can be absorbed effectively
from the skin. The drug is applied the skin in the form
of a patch having the drug container which releases
the drug at a constant rate.
Advantages
1. Prolonged and slow action
2. Can be removed when it is not required.
94. Transmucosal Administration
Sublingual route: A number of drugs can be absorbed
from the thinner portion of oral mucosal. The drug is
kept in the form of tablet or powder under the tongue.
Advantages
1. It is rapidly absorbed it bypasses liver and first pass
metabolism.
2. Easy procedure
3. Quick action
96. Rectal administration
Rectum can serve as useful site for drug administration
especially in unconscious patients and if nausea and
vomiting are severe.
Highly lipid soluble drugs are readily absorbed by
rectal route.
97. Topical
It is employed for local action of drugs; the various
preparations for topical use are ointment, creams,
lotions and paints, eye drops, ear drops, and nasal
drops.
102. Continue
NSAIDS, also known non-narcotic, non Opiod or
aspirin like analgesics because of:
1. They donot depress CNS
2. They donot produce physical dependence
3. They have no abuse liability
4. They are weaker analgesics
5. They are more commonly employed and many are
OTC.
106. Mechanism of action
NSAIDS blocked prostaglandin generation.
Beneficial actions due to prostaglandin synthesis
inhibition:
1. Analgesia
2. Anti-pyretic
3. Anti-inflammatory
4. Anti-thrombotic
5. Closure of ductus arteriosus in newborn.
107. Continue
Shared toxicities due to prostaglandin synthesis
inhibition:
1. Gastric mucosal damage
2. Bleeding, inhibition of platelet function.
3. Limitation of renal blood flow, sodium and water
retention.
4. Delay, prolongation of labour
5. Asthma and anaphylactoid reactions in susceptible
individuals.
109. Aspirin
Aspirin is acetylsalicylic acid and it is rapidly converted
in the body to salicylic acid which is responsible for
most of the actions.
It is one of the most oldest analgesic anti-
inflammatory drugs and is a still widely used.
115. Ibuprofen
Ibuprofen was the first member of this class to be
introduced in 1969 as a better tolerated alternative to
aspirin.
Inhibit prostaglandin synthesis.
It is used for analgesic, anti-inflammatory and anti-
pyretic.
Inhibition of platelet aggregation is short lasting with
ibuprofen
119. Diclofenac sodium
It is well absorbed drug
It inhibits prostaglandin synthesis.
Metabolized and excreted both in urine and bile.
The plasma half life is 2 hours.
Available as 50mg TDS, then 75mg BD oral.
122. Indomethacin
It is a potent anti-inflammatory drug with prompt
anti-pyretic action.
Indomethacin relieves only inflammatory or tissue
injury related pain.
It is a highly potent inhibitor of prostglandin synthesis.
Indomethacin is well absorbed orally and rectal
absorption is low.
126. Metamizol (Dipyrone)
Metamizol is a derivative of amidopyrine is a potent
and promptly acting analgesic and antipyretic, but
having poor anti-inflammatory effect.
It can be given:
1. Orally
2. IM
3. IV
127. Continue
Metamizol has:
1. Pain during injection
2. Gastric irritation
Few cases of agranulocytosis were reported and
metamizol is banned in USA and Europe.
Available 0.5-1.5mg oral/IM/IV.
128. NSAIDS case studies
ID/CC: A 22 year old white female who is a professional
skier presents to the emergency room complaining of
severe malaise, dizziness, jaundice, very low urinary
volumes and fatigue.
HPI: Following a recent skin accident, in which she
sprained her shoulder and knee, she took a total of 20
tablets of diclofenac over a 3-day period.
129. Continue
PE: Mild hypotension, no fever, severe dehydration
and tenderness to palpitation in epigastric area.
Labs: Hyperkalemia
Treatment: volume replacement, immediate
withdrawal of NSAIDS, supportive therapy, metabolic
correction, and avoidance of all nephrotoxic
medications.
130. Continue
Discussion: Use of NSAIDS, such as diclofenac can
lead to acute renal failure via two mechanisms.
Unopposed renal vasoconstriction by Angiotensin II
and norepinephrine.
Reduction in cardiac output caused by the associated
rise in systemic vascular resistance.
Thus, inhibition of prostaglandin synthesis by an
NSAIDS can lead to reversible renal ischemia, a
decline in glomerular hydrostatic pressure (the major
driving force for glomerular filtration) and acute renal
failure.
131. Indomethacin case study
ID/CC: A 28 year old male comes to his family
medicine clinic and complains of increased bruising
over the past 3 days as well as bleeding from the gums
while brushing his teeth.
HPI: The patient is an amateur weight lifter who
recently tried to lift an excessive amount of weight but
strained a muscle and has been taking Indomethacin
for pain.
PE: Normal
Labs: increased PT
132. Continue
Treatment: Discontinue Indomethacin; vitamin K
may be used in patients with an elevated PT.
Discussion: NSAIDS are extensively metabolized and
protein bound. NSAIDS inhibit the COX enzymes,
there by inhibiting prostaglandin production, which in
turn produces their anti-pyretic, anti-inflammatory
and analgesic effects. Moderate doses of NSAIDS can
bring out subclinical platelet defects in otherwise
healthy individuals.
135. These are drugs that we use respiratory infections
including upper and lower respiratory infections.
Introduction
136. Any substance capable of reducing the physiologic and
pharmacological effects of histamine.
Histamine is a bodily substance that performs many
functions.
Anti-histamines
137. CNS transmission
Dilation of capillaries
Contraction of smooth muscles
Stimulation of gastric secretion
Acceleration of the heart rate
Continue
138. There are two types of cellular receptors for
histamine:
1. H1 receptor
2. H2 receptor
Continue
139. Antihistamines are drugs that directly compete with
histamine for specific receptor , for this reason they
call antagonists.
H2 antagonists include
1. Cimetidine
2. Ranitidine
3. Famotidine
4. Nizatidine
Continue
141. They are greatest value in the treatment of nasal
allergies.
They are used for palliative therapy of common colds
They are used to prevent nausea and vomiting, for
motion sickness
They reduce nasal, salivary and lacrimal gland
secretion.
Proved to be safe and effective as sleep aid.
Therapeutic Uses
142. Work by inhibiting the action of histamine through
out the body.
Prevent stimulation of chemo trigger receptor zone
(CTZ).
Mechanism of actions
144. Has the longest half-life (20-60 hrs)
Dosed once a day
Has very poor ant cholinergic activity.
Indicated for the treatment of seasonal variation
especially in allergy rhinitis.
Cautiously given with a patient who have liver
problem.
Contraindicated patients with hypersensitivity.
Astemizole
145. It is classified pregnancy category C.
Available in 10mg.
Recommended 10mg/day, given as a single dose.
Continue
146. It is a non-sedating antihistamine drug.
Used to relieve symptoms of seasonal allergies, hay
fever.
Classified pregnancy category B agent.
Contraindicated in patient shown hypersensitivity.
Available in 10mg tablet.
Recommended once a day.
Loratidine (claritin)
147. Terfenadine was the first non-sedating anti histamine
to come available.
Has short half life
Used to relieve the symptoms of seosonal allergic
rhinitis.
It is a pregnancy category C.
Available only for oral preparation.
Terfenadine (seldane)
148. Terfenadine it self comes 60mg tablet, the
combination product contains 60mg of Terfenadine
and 120mg of pseudoephedrine.
Usual recommended dosage is 60mg twice daily, BID.
Continue
149. Diphenhydramine is older and traditional anti-
histamine.
Has potent of ant cholinergic effect.
Classified pregnancy category B agent.
Contraindicated for
1. Hypersensitivity
2. Nursing mother
3. Neonates
Diphenhydramine (Benadryl)
150. Available oral, parentral, and topical preparations.
25mg-50mg cap oral
12.5mg/5ml syrup
10mg/ml- 50mg/ml injection
1%-2% cream topically
Continue
151. Available as 4mg, 8mg, and 12mg tablets.
Available as POM or OTC
Recommended oral dosage is 4mg ever 4 hrs or 6 hrs,
given with a full glass water.
It is a pregnancy category C.
Chlorpheniramine(priton)
152. Available as 2mg/5ml syrup and 4mg tablets.
It is recommended 4mg in TID, QID.
It is a pregnancy category B.
Cyproheptidine
153. It is a POM drug, available 50mg tablets.
Recommended oral adult dosage is 50mg-100mg every
4 to 6 hours.
Recommended in children for 25mg-50mg ever 6 or 8
hour.
Taken half an hour before the travel.
It is rated in pregnancy category B.
Dimenhydrinate
154. It is an OTC drug available as 1.25mg/5ml syrup and
2.5mg tablet.
The recommended adult dosage is 2.5mg every 4 to 6
hour, taken with a full of glass water.
It is rated in pregnancy category B.
Triprolidine (actidil)
155. It is a prescription drug available as 25 and 50mg/ml
injection, as a 6.25 and 25mg/ml syrup.
The recommended adult dosage is 12.5mg and 25mg
TID.
It is rated pregnancy category C.
Promethazine (phenergan)
156. It is a prescription drug available as 0.67mg/5ml syrup
and 1.34mg, 2.68 mg tablets.
The recommended oral adult dosage is 1.34mg and
2.68mg TID.
It is rated in pregnancy category B agent.
Clemastine (tavist)
157. Coughing is a normal physiologic function and serves
the purpose of removing potentially harmful foreign
substance and excessive secretions from the
respiratory tract.
The cough reflex is stimulated when receptors in
bronchi, alveoli, and pleura are stretched.
Anti-tissuves
158. 1. Upper or lower respiratory tract infections. E.g
appropriate antibiotics
2. Smoking. E.g cessation of smoking
3. Pulmonary tuberculosis. E.g antitubercular drugs.
4. Asthmatic cough. E.g inhaled beta2
agonist/corticosteroids.
5. Rhinitis. E.g avoidance in precipitating factor,
corticosteroids or H1 blockers.
Etiology of cough
160. 1. Pharyngeal demulcents
a. Lozenges
b. Cough drops
c. Glycerine
d. Linctuses containing syrup
2. Expectorants
a. Sodium or potassium citrate
b. Potassium iodide
c. Guiphenesin
d. Ammonium chloride
Drugs for cough
161. 3. Antitussives
a. Codeine
b. Pholcodeine
c. Noscapine
d. Dextrometrophan
e. Chlophedianol
f. Chlorpheniramine
g. Diphenhydramine
h. Promethazine
Continue
163. Cough can be classified into:
1. Productive cough
2. Non-productive cough
Classification of cough
164. There are two main categories of these agents:
1. Narcotic agents
2. Non-narcotic agents
Classification of drugs
165. Narcotic agents have anti-tissuve effects.
They are effective in suppressing the cough reflex.
They are POM drugs.
Their use lead dependence
1. Codeine
2. Hydrocodeine
Narcotic Agents
166. Non-narcotic antitissuve drugs are less effective than
the narcotic ones.
They are available either alone or combination with
other agents, they are POM drugs.
1. Dextromethorphan
2. Benzonatate
Non-narcotic
167. The narcotic anti-tissuves codeine and Hydrocodeine
suppress the cough reflex through a direct action on
this cough center.
Non-narcotic drugs suppress the cough reflex by
anesthetizing (numbing) and thus keeping the cough
reflex from being stimulated in the medulla.
Mechanism of Actions
168. Anti-tissuves are primarily used to stop the cough
reflex, when the cough is non-reproductive and
harmful
Therapeutic Uses
170. Dextromethorphan is a non narcotic anti tissuve drug.
It is widely used because of safety, non-addicting and
does not cause respiratory depression.
It is a pregnancy category C.
Adult dose is 10-30mg q4h-q8h
It is contraindicated, hypersensitivity, headache and
asthma.
Dextromethorphan
171. It is a non narcotic anti-tissuve drug.
Anesthetizing or numbs the cough receptor.
Available only in a POM.
It is a pregnancy category C
Adult dose is 100mg TID.
Benzonatate (Tessalon)
172. It is a very popular narcotic anti-tissuve drug.
It is a potentially addictive.
Depress respirations and the CNS activity.
It is classified pregnancy category C.
Adult dose is 10-20mg q4h-q6h.
It is contraindicated:
1. Hypersensitivity
2. Respiratory depression
3. Seizure disorders
Codeine
176. These are drugs that are used for the lower respiratory
tract infections (LRTI):
1. Asthma
2. Emphysema
3. Chronic bronchitis
4. Chronic obstruction pulmonary disease (COPD).
Bronchodilators
177. Bronchodilators can be classified into based on their
mechanism of actions:
1. Beta-agonists
2. Xanthine derivatives
3. Corticosteroids
Continue
178. Beta-agonists are large group of drugs that are
commonly used during the acute phase of an
asthmatic attack.
They are agonists or stimulators of the sympathetic
nervous system.
Beta-agonists
179. There are three types of beta-agonist bronchodilators:
1. Non-selective adrenergic drugs, which stimulate the
alpha, beta one (cardiac), and beta two (respiratory)
receptors.
E.G, epinephrine
2. Non- selective beta adrenergic drugs, which stimulate
both beta one and beta two receptors. E.g
isoproterenol
Continue
180. 3. Selective beta two drugs, which only stimulate the
beta two receptors.
E.g Albuterol (Salbutamol)
Continue
181. Bronchodilators begins at the speacific receptors.
stimulating receptors, dilate the airways.
Mechanism of Action
182. It is a commonly used drug in acute asthma attacks.
Used for prevention of acute attacks
It is a pregnancy category C drug.
It is a prescription drug
Available 2-4mg tablet, 2mg/5ml syrup, 0.083%
solution and 0.5 % concentration solution.
Albuterol (Salbutamol)
183. Pediatric dose is 0.1mg/kg TID or 2mg Tid or Qid.
Adult dose is 2 inhalational q4h-q6h.
Available in the forms of:
1. Aerosol
2. Solution
3. Powder
Continue
184. Metaproterenol is a synthetic sympathomimetic
bronchodilator that stimulates both beta one and beta
two receptors.
It is classified pregnancy category C.
It is available as a POM drug
Contraindicated:
1. Hypersensitivity
2. Narrow angle glaucoma
Metaproterenol
185. Orally it came's as a 10mg/5ml solution, 10mg-25mg
tablets.
Inhalation 0.65mg per spray
Peadtric dosage is 10mg Tid, Qid.
Adult dosage20mg Tid, Qid.
Continue
186. Epinephrine, ephedrine, ethylnorepinephrine are all
beta-agonist bronchodilators, that work by stimulating
both beta and alpha receptors.
Epinephrine is available with or with out prescription.
Subcutaneous 10 microgram/kg/dose
Aerosol 0.2mg per inhalational Prn.
Epinephrine
187. Xanthenes are natural alkaloids that consists of:
1. Caffeine (stimulant)
2. Theobromine (diuretic)
3. Theophylline
Xanthenes are used for prevention and treatment of
asthmatic patients.
Xanthenes are used as a bronchodilators.
Xanthine Derivatives
188. Theophylline is the most commonly used drug for all
xanthine derivatives as well as all bronchodilators.
It is used for chronic respiratory disorders and relief of
mild to moderate acute asthma.
It is classified in a pregnancy category C.
Contraindicated in patients with hypersensitivity.
Theophylline is available oral, rectal, parenteral, and
topical.
Theophylline
189. Pediatric, usual dose is 2.5 mg/kg in q6h
Adult dose is 160mg q6h
Dosage forms
1. Capsules 100mg- 200mg
2. Tablets 100,125, 200, 250, and 300mg.
3. Injection 25,2500, 5000mg/ml
4. Suppository 250mg and 500mg.
Continue
190. They all cause bronchodilation by increasing the levels
of the energy producing substance.
Increase levels of CAMP produce competitively inhibit
phosphodiestrase enzyme.
Mechanism of Action
191. Corticosteroids are used for in the treatment of
chronic asthma for their anti-inflammatory effects
which lead to decreased airway obstruction.
Corticosteroids are used also for prophylactic in acute
attacks.
The corticosteroids do this by preventing the release of
substances that produce inflammation of lungs.
Corticosteroids
192. Corticosteroids administered inhalation have an
advantage over orally administered corticosteroids in
that their action is limited to the topical site of action.
Drugs of corticosteroids are:
1. Beclomethasone
2. Dexamethasone
3. Triamcinolone acetonide
4. Flunisolide
Continue
193. Pregnant women
Lactating women
Children below 2 years
Contraindicated
195. Administered by oral and inhalation.
Used for the treatment of bronchial asthma.
Beclomethasone oral solution or rectal suspension has
also been used in the management of inflammatory
diseases of the gastrointestinal tract (GIT).
The primary sites of Beclomethasone are bronchi and
bronchioles.
It is rated in a pregnancy category C.
Beclomethasone
196. Cromolyn is a mast cell stabilizer indicated for the
prevention of bronchospasm and bronchial asthmatic
attacks.
It is classified pregnancy category B agent.
Available for both oral and ophthalmic administration
as well as nasal and oral inhalation.
It is a prescription drug, POM.
Cromolyn
197. Available in nasal solution 5.2 mg per metred spray.
Ophthalmic solution 4 %
Capsule 100mg
Adult dose is 5-20mg several times in a day, nasal
solution 5.2mg 3-6 times a day.
Continue
198. Nedocromil is indicated for the prevention of
bronchospasms and bronchial asthma attacks.
It is a pregnancy category B agent.
Only available as an aerosolized inhaler.
It is used for mild to moderate bronchial asthma.
It is available only in POM.
Adult dose is 14mg per day.
Nedocromil
202. Continue
Antibiotics are drugs of pertaining ability to destroy or
interfere with the development of a living organism.
Antibiotics can be classified into:
1. Bacteriostatic
2. Bactericidal
203. Sulfonamides
Sulfonamides are chemically related group of
antibiotics that are all synthetic derivatives of
sulfonamide.
They were one of the first group of drugs used as
antibiotics and some of the more commonly
prescribed agents.
204. Continue
These antibiotics achieve very high concentration in
kidneys through which they are eliminated. There fore
they are primarily used for the treatment of urinary
tract infections (UTI).
Sulfonamides are also used in the treatment of
rheumatoid arthritis, in addition they may be
combined with other antibiotics to increase their
antibiotic potency.
208. Mechanism of action
Sulfonamides donot actually destroy bacteria but
inhibit their growth.
They inhibit the growth of susceptible bacteria by
preventing the synthesis of folic acid.
The enzyme dihydrofolic acid DHF, synthase converts
para-amino benzoic acid PABA to DHF, which
subsequently converts into tetrahydrofolic acid THF.
209. Therapeutic Uses
Sulfonamides are used for the treatment of:
1. Urinary tract infections caused by, enterobacter spp,
klebsiella spp, proteus vulgaris, & staphylococcus
aureus.
2. Nocardiosis
3. Infected burns and leg ulcers (silver sulfadiazine)
4. Inflammatory bowel disease (sulfasalazine)
211. Sulfamethoxazole
Sulfamethoxazole is an intermediate acing
sulfonamide antibiotic.
Because it is eliminated by means of kidneys and
reaches very high concentrations there, it is commonly
used to treat urinary tract infections caused by
susceptible organisms.
It is combined phenazopyridine (analgesic) that affects
the mucosa of UTI.
212. Continue
Sulfamethoxazole by it self comes as a 500mg/5ml oral
suspension and 500mg tablet.
It is a pregnancy category C.
213. Co-trimaxazole
Co-trimaxazole is a combination of Sulfamethoxazole and
Trimethoprim.
The optimum synergistic in vitro effect against most
susceptible bacteria is achieved with 5: 1 ratio of
Sulfamethoxazole and trimethoprim.
Has an half life of 10 hour.
Used for UTI caused by susceptible bacteria, pneumocystis
carinii pneumonia.
Used for ear infection (otitis media)
Used for bronchitis
Used for STD including gonorrhea and syphilis.
214. Continue
Available 40mg/5ml oral suspension
Available 80mg trimethoprim & 400mg
Sulfamethoxazole= 480mg co-trimaxazole.
Available 180mg trimethoprim & 800mg
Sulfamethoxazole = 980mg co-trimaxazole.
Available 16mg/ml trimethoprim & 80mg/ml
Sulfamethoxazole= 96mg/ml injection.
215. Sulfisoxazole
Sulfisoxazole is a short acting sulfonamide antibiotic
that is primarily used urinary tract infections.
Used for ear infection (otitis media) in small children.
It is a pregnancy category C agent.
Available 500mg tablet & 500mg/5ml suspension.
216. Penicillin's
The penicillin's are very large group of chemically
related antibiotics that are derived from a fungus or
mold, often seen on bread or fruit.
The penicillin's may also be called beta-lactam, a term
which refers to their chemical structure.
217. Continue
The penicillin's was first introduced on the market in
the early 1940 and to this day they have remained very
effective and safe antibiotics.
They are bactericidal and can kill a wide variety of
gram positive bacteria
Half life of penicillin's is 2h approximately.
218. Classification of drugs
The penicillin's can be divided into:
1. Natural penicillin's
2. Penicillinase resistant penicillins
3. The amino-penicillins
4. The extended spectrum penicillin's
219. Mechanism of action
Penicillin's involves several steps that together result in
the inhibition of bacterial cell wall synthesis.
They block penicillin binding proteins (PBP), by
inhibiting peptidoglycan in the cell wall bacteria.
225. Penicillin G Benzathine
Given IM injection
Long acting drug
Expected to work over the course for several days.
226. Penicillin G K+ & Na
Commonly administered IV for the treatment of life
threatening illnesses such as:
1. Septicemia
2. Meningitis
3. Pericarditis
4. Severe pneumonia
227. Aminopenicillins
There are three aminopenicillins:
1. Amoxicillin
2. Ampicillin
3. Bacampicillin
Because of the presence of a free amino group on the
penicillin's nucleus, the aminopenicillins have
enhanced activity against gram negative bacteria.
228. Continue
Amoxicillin is an analogue of ampicillin and
becampicillin is a prodrug of ampicillin.
The aminopenicillins are contraindicated:
1. Hypersensitivity
They are rated in a pregnancy category B drugs.
231. Ampicillin
Ampicillin is the prototypical amino penicillin, that
has amino group.
It is available in three different forms:
1. Anhydrous
2. Trihydrate
3. Sodium
Anhydrous and trihydrate Ampicillin are
administered orally.
232. Continue
Ampicillin sodium is given parenterally.
Available 250mg, 500mg capsules, 250mg/5ml
suspension, 125, 250, 500, 1000, 2000, 10,000mg vial for
injection.
Adult dosage is PO: 250mg- 500mg Qid, IM/IV:
250mg-500mg Qid.
233. Penicillinase Resistant
Penicillin's
These congeners have side chains that protect the
beta-lactam ring from attack by staphylococcal
penicillinase.
However this also partially protects the bacteria from
the beta lactam ring. Their only indication is infectious
caused by penicillinase producing staphylococci, for
which they are the drugs of choice except in areas
where methicillin resistant staph aureus (MRSA) has
become prevalent.
234. Methicillin
It is highly penicillinase resistant but not acid
resistant, must injected. it is also an inducer of
penicillinase production.
The MRSA have altered PBPs which donot bind
penicillins.
The drug of choice for these organisms is
vancomycin/linezolid, but ciprofloxacin can also be
used.
Haematuria, albuminuria, and nephritis are the side
effects of methicillin.
235. Cloxacillin
It has an isoxazolyl side chain and is highly
penicillinase as well as acid resistant.
It is more active than methicillin against penicillinase
producing staph.
Cloxacillin is incompatibly but dependably absorbed
from oral route, especially if taken in empty stomach.
Plasma half life is about 1 hour.
Elimination occurs primarily by kidney, also partly by
liver.
It is available 0.25g, 0.5g cap and injections.
236. PROCAINE PENICILLIN ALLERGIC REACTION
ID/CC: A 21 year old male comes to the health clinic
because of the development of fever, marked itching
all over his body, generalized rash with joint swelling
and difficulty breathing.
HPI: he just returned from a trip abroad, where he had
developed a purulent urethral discharge and went to a
local doctor who gave him two pills of procaine
penicillin.
PE: mild hypotension, mild cyanosis and difficulty
breathing.
Imaging: CXR is normal
237. Continue
Treatment: Subcutaneous epinephrine, oxygen,
hydrocortisone, antihistamines. Maintain airway and
provide assisted ventilation if necessary. Severe
reactions may result in laryngeal obstruction,
hypotension and death.
238. Continue
Discussion: Penicillin’s are antimicrobial drugs that
block cell wall synthesis by inhibiting peptidoglycan
cross linking; they are bactericidal for gram positive
cocci and rods, gram negative cocci. Most adverse
reactions to penicillin are allergic reactions that result
when one of it is metabolites acts as hapten.
Anaphlytic reaction involves antigen reacting with IgE
on presensitized mast cells and basophils, it is usually
severe and immediate.
239. METHICILLIN RESISTANCE STAPHYLOCOCCUS AUREUS (MRSA)
ID/CC: A 25 year old male presents with spiking fevers, malaise,
left sided chest pain and cough.
HPI: His symptoms started two weeks ago and have
progressively worsened despite a full course of oral antibiotics.
He also reports a history of prior IV drug abuse.
PE:VS: Fever (39 centigrade), tachycardia (HR 105), tachypnea.
PE: amphoric, breath sounds heard over left lower lobe; S1 & S2
normally heard without murmurs, gallops or rubs.
Labs: induced sputum cultures grew methicillin resistant
staphylococcus aureu.
Imaging: XR, chest: 2 by 3cm cavity in left lower lobe of lung
with air fluid level. CT, chest: confirmed a left lower lobe lung
abscess.
240. Continue
Treatment: Intravenous Vancomycin therapy, add
aminoglycoside for synergistic bactericidal effect.
Discussion: Antibiotic resistant is continuing to
increase in both the hospital and the community.
Major resistant nosocomial organisms include
s.aureus, klebsiella, and pseudomonas. MRSA is
becoming widespread in a number of communities
and is more commonly seen in IV drug abusers,
patients with recent hospitalizations.
241. Cephalosporin's
The cephalosporin's are semi-synthetic antibiotic
derivatives of cephaloporin C.
These chemically altered derivatives of this fungus are
broadly referred to as cephalosporin's and they are
structurally and pharmacologically related to the
penicillin's.
Cephalosporin's have a broad spectrum of bacteria.
242. Continue
The safety profiles, contraindications and pregnancy
ratings of cephalosporin's are very similar to those of
penicillin's.
Because of cephalosporin's are chemically very similar
to penicillin's, a person who has had an allergic
reaction to penicillin's have also allergic reaction in
cephalosporin's, this is referred to as cross sensitivity.
243. Continue
Cephalosporin's of all generations are very safe agents
that are categorized as pregnancy category B agents.
They are contraindicated:
1. Hypersensitivity
2. Younger than 1 month old
244. Classification of Drugs
Cephalosporin's can be classified into:
1. First generation
2. Second generation
3. Third generation
4. Fourth generation
246. Continue
First generation are usually active against gram
positive bacteria and have limited activity against gram
negative bacteria.
They are available both parenteral and oral.
247. Cefazolin sodium
First generation of cephalosporin
Excellent coverage against gram positive and poor
coverage of gram negative.
Only available in parenteral formulation that comes
500-1000mg vials for IM or IV injection.
Adult dosage is IM/IV: 250mg-1g q8h-q12h.
249. Continue
The second generation cephalosporin's have similar
coverage against gram positive organisms but
enhanced gram negative bacteria.
They include both parenteral and oral formulations.
The second generation cephalosporin's are also
excellent prophylactic antibiotics.
250. Continue
The qualities that make them excellent prophylactic
agents are:
1. Safety profile
2. Broad range of organisms they can kill
3. Relatively low cost
251. Cefoxitin
It is a parenteral second generation cephalosporin.
Cefoxitin has been used extensively as a prophylactic
antibiotic in patients undergoing such surgical
procedures especially in abdominal and colorectal
operations.
It is rated pregnancy category B.
Available only in parenteral formulations 1,2, 10g vials
for injection
254. Ceftriaxone
Ceftriaxone is a parenterally administered third
generation cephalosporin that differs from the other
agents in that it has a very long half life that allows it
to be given once a day.
It can be given both intravenously and
intramuscularly.
It can easily pass meningitis and BBB, making it an
excellent agent for the treatment of CNS infection.
255. Continue
Available 250, 500mg, 1, 2, 10 gram vials.
Adult dosage is: IM/IV 1-4 g/day as a single dose or
divided doses.
256. Tetracycline's
The tetracycline's are small chemically related group of
five antibiotics, three of which are naturally occurring
and two of which are semi-synthetic.
They are derivatives of streptomyces organisms.
Tetracycline's can only inhibit the growth of bacteria,
they cannot kill bacteria, therefore they are considered
bacteriostatic.
261. Side-effects
Discoloration of teeth
Tooth enamel hypoplasia
Retard fetal skeletal development
Photosensitivity
Alteration of the intestinal flora
Diarrhea
Gastric upset
Reduced bacterial vitamin K synthesis
262. Doxycycline
Doxycycline is a semi synthetic tetracycline antibiotic.
Doxycycline comes in the following three different salt
forms:
1. Calcium
2. Hyclate
3. Monohydrate
263. Continue
It is useful in the treatment of rickettsial infections,
gonorrhea and many gram negative infections.
It comes orally as a 25 and 50mg/5ml oral suspension,
50, 100mg capsules and 100, 200mg per ml injections.
It is rated in a pregnancy category D drug.
264. TETRACYCLINE RASH
ID/CC: A 19 year old red haired female visits her
dermatologist at a local clinic because of a rash that
appeared after she spent the sunny weekend hiking
without sun block protection.
HPI: Two months ago, her dermatologist put her on
the low dose tetracycline to prevent acne.
PE: Normal
Labs: Mild proteinuria
265. Continue
Treatment: Sun protection, both mechanical and
pharmacological, while taking tetracycline.
Discussion: Tetracycline’s are bacteriostatic
antibiotics that bind to 30s ribosomal subunit,
blocking synthesis of protein. If they are taken with
alkaline foods such as milk and antacids, GI
absorption is decreased. Tetracyclines are used
therapeutically and prophylactically for chylamdial
infections, lyme disease, acne and cholera.
266. Aminogylcosides
Aminoglycosides are group of natural and semi-
synthetic antibiotics that destroy bacteria, rather than
inhibit their growth, so they are bactericidal.
They are derived from streptomyces organisms.
They are not given orally because of their poor oral
absorption.
267. Continue
They can kill both gram positive and gram negative
bacteria but are customarily used to kill gram negative
such as, pseudomonas, E. coli and klebsiella.
The aminogylcosides work in a way that is similar to
that of tetracycline's in that they also bind to
ribosomes and thereby prevent protein synthesis in
bacteria.
268. Continue
The aminogylcosides have been shown to cross the
placenta and cause fetal harm when administered to
pregnant women.
The pregnancies categories of the various
aminogylcosides are as follows:
1. Gentamycin, neomycin: pregnancy category C
2. Tobramycin,Amikicin,kanamycin:pregnancy D
3. Streptomycin: pregnancy category B
270. Preparations Available
Amikacin(generic, Amikin): Parenteral: 50, 250 mg
(in vials) for IM, IV injection
Gentamicin(generic, Garamycin): Parenteral: 10, 40
mg/mL vials for IM, IV injection
Kanamycin(Kantrex): Oral: 500 mg capsules,
Parenteral: 500, 1000 mg for IM, IV injection; 75 mg
for pediatric injection
Neomycin(generic, Mycifradin): Oral: 500 mg tablets;
125 mg/5 mL solution
271. Continued
Netilmicin (Netromycin): Parenteral: 100 mg/mL for IM,
IV injection
Paromomycin(Humatin): Oral: 250 mg capsules
Spectinomycin(Trobicin): Parenteral: 2 g powder to
reconstitute for 400 mg/mL IM injection
Streptomycin(generic): Parenteral: 400 mg/mL for IM
injection
Tobramycin(generic, Nebcin): Parenteral: 10, 40 mg/mL
for IM, IV injection; powder to reconstitute for injection
Solution for inhalation (TOBI): 300 mg in 5 mL sodium
chloride solution
272. Mechanism of action
Aminoglycosides kill bacteria by binding and
disrupting protein synthesis in bacteria specifically
they do this by binding to both 30s and 50s ribosomal
subunit.
274. Gentamycin
Gentamycin is a naturally occurring aminoglycoside
that is obtained from cultures of micromonospora
purpurae.
It is one of the Aminoglycosides most commonly used
in clinical practice today.
It is classified pregnancy category C.
Available 10, 40mg/ml injection IM/IV, 10, 60, 80 mg
per ml intravenous infusion.
275. Continue
Available 3% solution or ointment for ophthalmic.
Comes also 0.1% ointment for topical application on:
1. Superficial skin infection
2. Burns
3. Skin ulcers
276. GENTAMICIN SIDE EFFECTS
ID/CC: A 34 year old women presents with her family
practitioner complaining of hearing loss, vertigo and
inability to walk properly due to lack of balance.
HPI: she took IV Gentamicin for 10 days
PE: Well hydrated, oriented and cooperative
Imaging: normal
277. Continue
Treatment: Discontinuation of the drug, supportive
therapy.
Discussion: Gentamicin is an aminoglycoside and
thus shares the Ototoxicity and Nephrotoxicty of
streptomycin, kanamycin, Amikacin, and tobramycin.
Ototoxicity is mainly cochlear and marked by ataxia
and vertigo. Nephrotoxicity is minimized if care is
taken to hydrate the patient and keep serum levels
therapeutic.
278. Quinolones
The quinoline antibiotics are very potent broad
spectrum antibiotics.
They are bactericidal
The first of these agents to come available were:
1. Cinoxacin
2. Nalidixic acid
280. Continue
A fluorine atom was added on to the basic quinolone
structure to create these newer agents and increased
their anti-bacterial activity.
Because of chemical, these agents are sometimes
called fluoroquinolones.
281. Continue
The fluoroquinolones are active against a wide variety
of gram negative and selected gram positive bacteria.
Fluoroquinolones are primarily excreted by the
kidneys, which contain a high percentage of
unchanged drug, this makes them good for treating of
UTI.
282. Continue
Their use in children is not currently recommended
because they have been shown to suppress growth in
laboratory animals.
283. Mechanism of action
Quinolone antibiotics destroy bacteria by altering
DNA and they accomplish this by interfering with
DNA gyrase, enzyme necessary for the synthesis of
bacterial DNA, if bacteria cannot produce DNA they
die.
285. Ciprofloxacin
Ciprofloxacin was one of the first potent
fluoroquinolones to come available.
First marketed in an oral form and advantage of
convenience of oral preparation plus excellent
bioavailability.
Effective against to kill gram negative bacteria.
Orally comes 250, 500, 750mg tablet, parenterally
comes 200, 400mg.
The common dosage is 250mg-750mg Tid, Bid.
286. FLUOROQUINOLONE SIDE
EFFECTS
ID/CC: A 21 year old college baseball player restarted
his training 3 days ago, running 1600 meters a day in
preparation for the upcoming state tournament,
yesterday he hit a home run and started off to first
base when he suddenly fell to the ground and couldn’t
work due to acute pain.
HPI: He had spent 4 weeks in the hospital recovering
from perforated appendicitis where he received IV
ciprofloxacin for 2 weeks due to surgical wound
infection with pseudomonas aeruoginosa that was
resistant to all other antibiotics.
287. Continue
PE: Surgical wound completely healed with no
evidence of infection or postincisional hernia; penrose
drain orifice within normal limits; inability to
plantarflex left foot; Achilles tendon completely
severed.
Labs: CBC: no leukocytosis; no anemia. SMA-7
normal. UA: normal.
Imaging: CXR/KUB: within normal limits.
Micro Pathology: Achilles tendon shows
inflammatory neutrophilic infiltrate with areas of
heamorrhage and necrosis.
288. Continue
Treatment: Surgical repair.
Discussion: Fluoroquinolones such as ciprofloxacin
and Norfloxacin are bactericidal antibiotics that are
active against gram negative rods, including
pseudomonas; they are also active against Neisseria
and some gram positive organisms. They act by
binding DNA gyrase. Side-effects include damage to
cartilage, tendonitis, and tendon rupture; they also
produce gastric upset and nausea and may cause super
infection.
289. Macrolides
The Macrolides are a large group of antibiotics that
first came available in the early 1950s with the
introduction of erythromycin.
Macrolides have a macrocyclic lactone.
Macrolides are considered bacteriostatic but in high
concentration may be bactericidal in some susceptible
bacteria.
Macrolides are POM drugs.
Macrolides are rated pregnancy category C.
294. Mechanism of action
They bind 50s ribosomal subunit inside the cells of
bacteria and by doing so prevent the production of the
bacterial protein needed for bacteria to grow, with the
result that bacteria eventually will die.
295. Antibacterial spectrum
It is narrow, includes mostly gram positive and a few
gram negative bacteria.
It is highly active in the following bacteria's:
1. str. pyogenes
2. Str. Pneumoniae
3. N. gonorrhoeae
4. Clostridia
5. C. dipthteriae
296. Uses
1. As an alternative to penicillin: streptococcal
pharyngitis, tonsillitis, community acquired
respiratory infections caused by pneumococci and H.
influenzae, however many bacteria resistant to
penicillin are also resistant to erythromycin.
2. Diphtheria: erythromycin 250mg Qid, acute stage as
well as for carriers 7 day treatment, antitoxin is the
primary treatment.
297. Continue
3. Tetanus: erythromycin 500mg is given Qid for 10 days
to eradicate clostridium tetani.
4. Syphilis and gonorrhea
5. Atypical pneumonia caused by mycoplasma
pneumoniae
6. Whooping cough: 1 to 2 week course of erythromycin
is the most effective treatment for eradicating
Pertussis from upper respiratory tract.
298. Continue
7. Chlamydia trachomatis infection of urogenital tract:
erythromycin 500mg QID for 7.
8. Penicillin resistant staphylococcal infections
9. Helicobacter pylori infection: Clarithromycin 500mg
in combination in Omeprazole 20mg, and amoxicillin
1g each administered twice a day for 10 to 14 days, is
effective for the treatment of peptic ulcer disease.
10. Mycobacterial infection: Azithromycin or
Clarithromycin are recommended for the first line of
prophylaxis and treatment of pulmonary disease. E.g
AIDS.
300. Drug-Drug Interactions
Clarithromycin and erythromycin inhibit CYP3A4.
erythromycin potentiates the effects of
Carbamazepine, corticosteroids, digoxin,
Theophylline, Warfarin.
301. Erythromycin
Most frequently prescribed macrolide antibiotic.
It comes in several different salt and dosage forms that
were developed to circumvent some of the drawbacks
it has chemically.
The absorption of oral erythromycin is enhanced if it
is taken on an empty stomach, but because of the high
incidence of stomach irritation, many of the agents are
taken after meal or snack.
302. Continue
Dosage range is:
1. children: 30-100mg/kg/day divided dose
2. Adult: 500mg as single dose or Bid
304. Vancomycin
It is a natural bactericidal antibiotic structurally
unrelated to any other commercially available
antibiotics.
It is a glycopeptide antibiotic discovered in 1956.
It destroys bacteria by binding to the bacterial cell wall
producing immediate inhibition of cell wall synthesis
and death.
It is the antibiotic of choice for the treatment of
MRSA.
306. Continue
The parenteral form is indicated for the treatment of
bone and joint infections and bacterial blood stream
infections caused by staphylococcus spp.
Classified pregnancy category B.
Caution use:
1. Renal dysfunction
2. Hearing loss
3. Elderly patients
307. Continue
Contraindicated for hypersensitivity
Available 125, 250mg capsules and 500mg, 1g for
intravenous infusions.
Adult dosage is 0.5-2g per day in Tid for 7-10 days.
308. Mechanism of action
Vancomycin inhibits the cell wall synthesis by binding
with high affinity, D-alanyl D-alanine.
Vancomycin is a bactericidal.
309. Toxicity
Systemic toxicity of Vancomycin is high. It can cause
plasma concentration dependant nerve deafness which
may be permanent.
Kidney damage is also dose related.
Skin allergy and fall of blood pressure during IV
injection.
Rapid IV injection has caused chills, fever and intense
flushing-Red man syndrome (an adverse anaphlytical
reaction to Vancomycin therapy causing pruritis,
flushing of the head and the upper part of the body,
the condition is caused by the release of histamine).
310. Uses
MRSA
Bacterial meningitis combination therapy with
Ceftriaxone or Cefotaxime.
Used for dialysis patients
Those undergoing chemotherapy for cancer patients.
Penicillin allergic patients
311. Chloramphenicol
Chloramphenicol was initially obtained from
streptomyces venezuelae in 1947.
It was soon synthesized chemically and the
commercial product now is all synthetic.
It has a nitrobenzene substitution, which is probably
responsible for the antibacterial activity and it is
intensely bitter taste.
313. Mechanism of action
Chloramphenicol inhibits bacterial protein synthesis
by interfering with transfer of the elongating peptide.
It specifically attaches 50S ribosome.
314. Pharmacokinetics
Chloramphenicol is rapidly and completely absorbed
after oral ingestion.
Chloramphenicol is primarily conjugated with
glucuronic acid in the liver and little is excreted
unchanged in urine.
Plasma half life of chloramphenicol is 3-5 hours in
adults.
It is increased only marginally in renal failure.
315. Therapeutic Uses
Enteric fever- Typhoid
Pyogenic meningitis: Chloramphenicol 50-75mg/kg
per day may be used after the third generation of
cephalosporin's.
Anaerobic infections: Wound infections, pelvic and
brain infections.
Intraocular infections: Chloramphenicol is given
systemically.
316. Adverse Effects
Bone marrow depression
Hypersensitivity reactions like, fever, rashes, glossitis,
Nausea
Vomiting
Diarrhea
Pain on injection
Gray baby syndrome: the baby stop feeding, vomited,
hypothermic, abdomen distended, respiration become
irregular and gray cyanosis occur.
317. CHLORAMPHENICOL SIDE EFFECTS
ID/CC: A 31 year old truck driver visits a health clinic
in Buroa Togdheer region, complaining of recurrent
infections, excessive bleeding, weakness and anemia.
HPI: He travels the border of Ethiopia daily and eats
and sleeps there. He has had a typhoid fever three
times over the past five years, for which he has been
treated with high dose of chloramphenicol.
PE: Normal
Labs: Anemia
318. Continue
Treatment: Blood transfusions, cyclosporin for bone
marrow transplantation.
Discussion: Chloramphenicol is a bacteriostatic
antibiotic that acts by inhibiting peptidyl transferase
in the 50s ribosomal unit. It is active against anaerobes
and riclettsiae as well as against typhoid fever and
meningococcal. In infants they produce gray baby
syndrome. Owing to its potentially fatal side-effect of
Aplastic anemia, chloramphenicol is used primarily for
serious infections or acute salmonella typhi infection.
321. Fungal Infections
• Fungi are a very large and diverse group of
microorganisms that compromise both yeast and
molds.
• Yeast are single-celled fungi that reproduce by
budding and are actually very useful organisms. They
are used in baking and alcoholic beverages.
• Molds are multicellular and are characterized by
long, branching filaments called hyphae, which
entwine to form a (mat) called a mycelium. Some
fungi are part of the normal flora of the skin, mouth,
intestines, and vagina.
322. Continue
The infection caused by a fungus can also be called a
mycosis, but there are very few fungi that cause such
infections. Those that do are termed pathologic fungi,
and the infections they cause range in severity from
being mild and superficial to severe and life-
threatening.
323. Continue
• These infections can be contracted by several
different routes:
• Ingested orally
• Implanted under the skin after injury
• They can be inhaled
• There are four major general types of mycotic
infections:
• Systemic
• Cutaneous
• Subcutaneous
• Superficial
324. Continue
The most severe systemic fungal infections generally
afflict persons whose host defenses are compromised.
Commonly these are patients who have received organ
transplants and are on immunosuppressive drug
therapy, cancer patients and AIDS patients. These
may result in an over growth of candida albicans,
followed by the development of a systemic infection.
325. Drug Profile
• The drugs used to treat fungal infections are called
antifungal agents. Systemic mycotic infections and
some cutaneous or subcutaneous mycoses are treated
with oral or parenterally agents.
• One difficulty that has slowed the development of
new agents is that frequently the chemical
concentrations required for these experimental
agents to be effective cannot be tolerated by human
beings.
326. Drugs used in systemic mycosis
• Following is a list of those agents that have met with
success in the treatment of systemic and severe
cutaneous or subcutaneous mycoses:
• Amphotericin B
• Fluconazole
• Flucytocine
• Griseofulvin
• Itraconazole
• Miconazole
• Nystatin
328. Classification of Drugs
The antifungals agents can be broken down in to four
major groups based on their chemical structures:
Polyenes, e.g Amphotericin B and Nystatin
Flucytosine
Azoles, e.g Ketoconazole and Miconazole
Griseofulvin
329. Mechanism of action
The mechanisms of action of the various antifungal
agents differ depending on which of the four groups of
agents they belong to.
The polyenes act by binding sterols in the cell
membranes of fungi, the main sterol in the fungi is
ergosterol. The question is human being has sterol
then how do we prevent damage in the human cell?
330. Continue
• The answer of this question polyene antifungal do not
bind to human cell membranes, and therefore do not
kill human cells, because polyene has stronger
affinity for ergosterol than for cholesterol. Once the
polyene binds to the ergosterol, a channel forms in
the fungal cell membrane that allows potassium and
magnesium ions to leak out of the cell. This loss of
ions causes fungal cellular metabolism to be altered,
and hence death of the cell.
331. Continue
Flucytosine, also known as 5-fluorocytosine. Once
the 5-fluorouracil is inside the fungal cell, it
interferes with DNA synthesis by incorporating
itself in to the fungal pathway that produces DNA,
with the result that the DNA needed for the fungal cell
metabolism is lacking and the cell dies.
332. Continue
• Azoles act as either fungistatic or fungicidal agents,
depending on their concentration in the fungus.
Inhibit production of ergosterol and this allows
potassium to escape from the fungi cell membrane
and lastly fungi cell dies.
• Griseofulvin works by preventing mitosis or
reproduction of fungi by binding to microtubules. It
has also been proposed that Griseofulvin causes the
production of defective DNA, which is then unable to
replicate.
333. Therapeutic uses
used candiasis (oral, vaginal e.t.c)
used in Aspergillosis
used in histoplasmosis
used in fungal septicemia
used in Coccidiodomycosis
used in cryptococcal meningitis
334. Aspergillosis
Infection caused by the aspergillus fungus or one of it
is mold species.
Invasive aspergillosis is an opportunistic infection that
affects people with immunodeficiencies. the primary
infection is usually pneumonia, but the brain,
kidney, and heart valves may also be affected.
It is treated with I.V amphotericin B or long term
oral itracanazole.
335. Histoplasmosis
A systemic fungal respiratory disease caused by
histoplasma capsulatum. The reservoir for this fungus
is in soil with a high organic content, old chicken
houses.
It is a common opportunistic infection. Signs are
fever, anemia, enlarged spleen, leukopenia,
adrenal necrosis and pneumonia.
The treatment is amphotericin B or Ketoconazole.
336. Coccidiodomycosis
Infection with the pathogenic fungus coccidio-
immitis. Found in the soil. It is seen in earthquakes,
during construction. Persons who inhale the spores
may develop active or subclinical infection.
Treatment: most patients with primary infection
recover with out therapy. Amphotericin B is
recommended 1-3 months.
337. Blastomycosis
Infection caused by inhalation of the conidia of
blastomyces dermatitidis. This rare fungal infection
may produce inflammatory lesions of the skin
(cutaneous), lungs or generalized invasion of skin,
bones, CNS, and the kidney.
Treatment is amphotericin B and Ketoconazole.
338. Dermatophytosis
It is causes by a fungal parasite that grows the skin of
the body, and it is known as dermatophyte fungal
infection.
They cause skin diseases like eczema, tinea, ringworm.
The treatment is Griseofulvin or the azoles and
terbinafine.
339. Chromomycosis
A chronic fungal skin infection marked by itching
and warty plaques on the skin and subcutaneous
swelling of the feet and the legs and other exposed
areas.
Various fungus have been implicated including
phialophora verrucosa.
The treatment includes amphotericin B and
Flucytosine.
341. Amphotericin B
• It is obtained from streptomyces nodosus.
• The polyenes possess a macrocyclic ring, one side of
which has several conjugated double bonds and is
highly lipophilic, while the other side is hydrophilic
with many OH groups.
• Amphotericin B is active against a wide range of
yeasts and fungi candida albicans, histoplasma
capsulatum, cryptococcus neoformans, blastomyces
dermatitides, and coccidiodes immitis.
342. Continue
Amphotericin isn't orally absorbed.
It can be given orally for intestinal candisasis without
systemic toxicity.
Administered I.V as a suspension made with the help
of deoxycholate.
It gets widely distributed in the body, but the
penetration in CSF is poor.
343. Continue
• It is metabolized in the liver.
• It has half life of 15 days.
• Excretion occurs slowly both in urine and bile, but
urinary concentration of active drug is low.
• Orally can be administered 50-100mg QID.
• For i.v 0.3mg/kg or 0.7mg/kg.
• The total dose of amphotericin for majority of cases is
3-4g given over 2-3 months.
• Intrathecal injection of 0.5mg twice weekly has been
given in fungal meningitis.
344. Uses
• Amphotericin B can be applied topically for oral,
vaginal and cutaneous candisasis and otomycosis.
• It is the most effective drug for various types of
systemic mycosis and is the gold standard of
antifungal therapy. However, because of higher toxicity
of amphotericin B, the azole antifungals are now
preferred in conditions where their efficacy
approaches.
345. Drug interactions
Flucytosine has supra-additive action with
amphotericin B in the case of fungi sensitive to fungus.
Rifampin and Minocycline , though not antifungal
in their own right but potentiate amphotericin action.
347. AMPHOTERICIN B TOXICITY
• ID/CC: During ward rounds, a 28 year old HIV positive
female patient complains that after a period of
improvement since her administration 3 days ago, she
now feels very sick, with high fever, marked
lightheadedness, headache, and myalgias.
• HPI: She was admitted because of cryptococcal
meningitis and was started on amphotericin B.
348. Continue
PE: VS: tachycardia (HR 93); hypotension (BP 90/55);
fever (39.3 centigrade); tachypnea. PE: nuchal rigidity
resolved, mental status improved.
Labs: CBC: mild anemia; normal leukocytes. Lytes:
hypokalemia. BUN and creatinine moderately
elevated.
349. Continue
• Treatment: If the reaction is severe, it may be
necessary to lower the dosage of amphotericin B, use
a liposomal form, or change to Fluconazole.
Antipyretics, antihistamines, and corticosteroids may
lessen febrile symptoms; heparin can decrease the
risk of thrombophebitis.
• Discussion: The mechanism of action of
amphotericin B is by binding to ergosterol in fungi
and forming membrane pores. Toxicities include
arrhythmias, chills and fever, hypotension and
nepthrotoxicity.
350. Nystatin
It is obtained streptomyces nourseia.
Nystatin has similar structure with amphotericin B
and has the same pore-forming mechanism of action.
It is too toxic for systemic use and is only used
topically. It is not absorbed from skin, mucous
membranes, or the gastrointestinal tract.
351. Continue
Nystatin is active against most Candida species and is
most commonly used for suppression of local candidal
infections. Nystatin is used in the treatment of
oropharyngeal thrush, vaginal candidiasis.
It is available 1 lac U ,5 lac U vaginal tab, 1 lac U per g
for eye ointment. (1mg = 2000 U).
It is available orally as suspension, topically 2% cream.
352. Griseofulvin
Griseofulvin is a fungistatic and used is in the
treatment of dermatophytosis. Absorption is improved
when it is given with fatty foods. Griseofulvin is
deposited in newly forming skin where it binds to
keratin, protecting the skin from new infection.
353. Continue
It must be administered for 2-6 weeks for skin and hair
infections to allow the replacement of infected keratin
by the resistant structures. Nail infections may require
therapy for months to allow regrowth of the new
protected nail and is often followed by relapse.
354. Continue
It is dose is 125mg- 250mg QID with meals, duration
depends the location.
Body skin: 3 weeks, palms and soles: 4 to 6 weeks,
finger nails: 4 to 6 months, toe nails: 8 to 12 months.
355. Adverse effects and drug
interactions
Adverse effects include an allergic syndrome much like
serum sickness, hepatitis, and drug interactions with
warfarin and phenobarbital, oral contraceptives and
alcohols.
Griseofulvin has been largely replaced by newer
antifungal medications such as itraconazole and
terbinafine.
356. Flucytosine
Flucytosine is related to fluorouracil (5-FU). Its
spectrum of action is much narrower than that of
amphotericin B. It is well absorbed orally. It is poorly
protein-bound and penetrates well into all body fluid
compartments including the CSF. It is eliminated by
glomerular filtration. Toxicity is more likely to occur in
AIDS patients and in the presence of renal
insufficiency.
357. Continue
Flucytosine is converted intracellularly first to 5-FU
and then to 5-fluorodeoxyuridine monophosphate (F-
dUMP) and fluorouridine triphosphate (FUTP),
which inhibit DNA and RNA synthesis,
respectively.
358. Clinical use
Active against Cryptococcus neoformans, some
Candida species, and the dematiaceous molds that
cause chromoblastomycosis. Clinical use at present is
confined to combination therapy, either with
amphotericin B for cryptococcal meningitis or with
itraconazole for chromoblastomycosis.
359. Adverse Effects
The adverse effects of flucytosine result from
metabolism (intestinal flora) to the toxic
antineoplastic compound flucytosine. Bone marrow
toxicity with anemia, leukopenia, and
thrombocytopenia are the most common adverse
effects, with derangement of liver enzymes occurring
less frequently.
360. Azoles
Azoles are synthetic compounds that can be classified
as Imidazoles and Triazoles. The Imidazoles consist
of Ketoconazole, Miconazole, and Clotrimazole.
The triazoles include Itraconazole and Fluconazole.
361. Continue
Azoles are active against many Candida species,
Cryptococcus neoformans, the endemic mycoses
(blastomycosis, coccidioidomycosis), the
dermatophytes, and, Aspergillus infections
(itraconazole). Adverse Effects: The azoles are
relatively nontoxic.
362. Adverse effects
The most common adverse reaction is minor
gastrointestinal upset, Most azoles cause
abnormalities in liver enzymes and, very rarely, clinical
hepatitis.
363. Ketoconazole
It is the first orally effective broad-spectrum antifungal
drug, useful in both dermatophytosis and deep
mycosis.
Ketoconazole is less selective for fungal P450 than are
the Fluconazole and Itraconazole (inhibit mammalian
cytochrome P450 enzymes).
The usual dose is 200mg o.d or BD, higher doses are
some times required.
Available 2% shampoo, cream, lotion.
364. Clinical use
it has limited use because of the drug interactions,
endocrine side effects, and of its narrow therapeutic
range. Oral formulation that is best absorbed at a low
gastric pH. Ketoconazole is used in treatment of
mucocutaneous candidiasis and non-meningeal
coccidioidomycosis. It is also used in the treatment of
seborrheic dermatitis and pityriasis versicolor
(Topical/ shampoo).
365. Adverse effects
First, ketoconazole inhibition of human cytochrome
P450 enzymes interferes with biosynthesis of adrenal
and gonadal steroid hormones, producing significant
endocrine effects such as gynecomastia, infertility, and
menstrual irregularities.
366. Drug interactions
Second, the interaction with P450 enzymes can alter
the metabolism of other drugs, leading to enhance
toxicity of those agents:
1. Phenytoin 6. Nifedipine
2. Diazepam 7. cyclosporine
3. Haloperidol 8. Statins
4. Warfarin 9. protease inhibitors
5. Digoxin
Ketoconazole rises the blood concentration levels.
367. Ketoconazole side effects
ID/CC: A 23 year old marathon runner visits his sports
medicine doctor complaining of unsightly,
embarrassing growth of his right breast
(GYNECOMASTIA) as well as undue fatigue after
training and a slight yellowish hue in the eyes
(JAUNDICE).
368. Continue
HPI: Three months ago, he was put on daily oral
Ketoconazole because of he had been suffering from a
severe, refractory tinea corporis infection.
PE: VS: bradycardia; fever (38.1 centigrade). PE: slight
jaundice in conjunctiva, no lymphadenopathy, no neck
masses, cardiopulmonary exam normal; no
hepatomegaly; examination of skin reveals tinea
corporis covering intertriginous areas, buttocks and
scrotum.
369. Continue
Labs: AST and ALT increased, serum bilirubin level
increased.
Imaging: US, liver: mildly enlarged liver.
Treatment: Discontinue drug; substitute treatment
with alternative antifungal (e.g terbinafine).
370. Continue
Discussion: Ketoconazole is an imidazole that
inhibits fungal synthesis of ergosterol in membranes.
It is used for blastomycosis, coccidiomycosis,
histoplasmosis, and candisasis.
371. Continue
Major side effects are hepatic damage, Gynecomastia,
impotence (due to inhibition of testosterone
synthesis), inhibition of cytochrome P450, fever, and
chills. When taken with antacids or H2 receptor
blockers, it is absorption is decreased. It dramatically
increases cyclosporine levels.
372. Clotrimazole and miconazole
Clotrimazole and miconazole are available over-the-
counter and are often used for vulvovaginal
candidiasis. Oral clotrimazole troches are available for
treatment of oral thrush and are a pleasant-tasting
alternative to nystatin. In cream form, both agents are
useful for dermatophytic infections, including tinea
corporis, tinea pedis, and tinea cruris. Absorption is
negligible, and adverse effects are rare.
