1.

General Pharmacology

1. Which of the following is a prodrug?

a. Morphine
b. Enalapril
c. Acetaminophen
d. Ibuprofen
Answer: b. Enalapril
2. Which route of administration has the highest bioavailability?
a. Oral
b. Intravenous
c. Subcutaneous
d. Intramuscular
Answer: b. Intravenous
3. Phase I reactions in drug metabolism involve:
a. Conjugation
b. Oxidation
c. Acetylation
d. Methylation
Answer: b. Oxidation
4. The therapeutic index is defined as:
a. ED50 / LD50
b. LD50 / ED50
c. EC50 / ED50
d. ED50 / EC50
Answer: b. LD50 / ED50
5. The first-pass metabolism primarily occurs in the:
a. Kidney
b. Liver
c. Lungs
d. Stomach
Answer: b. Liver

2. Autonomic Nervous System

6. Which drug is a non-selective beta-blocker?

a. Propranolol
b. Atenolol
c. Metoprolol
d. Esmolol
Answer: a. Propranolol
7. The primary mechanism of action of Pilocarpine is:
a. Beta receptor stimulation
b. Muscarinic receptor agonism
 c. Alpha receptor antagonism
d. Nicotinic receptor antagonism
Answer: b. Muscarinic receptor agonism
8. Which drug inhibits acetylcholinesterase?
a. Atropine
b. Neostigmine
c. Pralidoxime
d. Adrenaline
Answer: b. Neostigmine
9. Clonidine acts by:
a. Blocking beta receptors
b. Stimulating alpha-2 receptors
c. Inhibiting norepinephrine reuptake
d. Blocking alpha-1 receptors
Answer: b. Stimulating alpha-2 receptors
10. Which adrenergic receptor causes bronchodilation?
a. Alpha-1
b. Alpha-2
c. Beta-1
d. Beta-2
Answer: d. Beta-2

3. Cardiovascular Drugs

11. ACE inhibitors reduce blood pressure by:

a. Inhibiting renin release
b. Blocking angiotensin II receptors
c. Inhibiting angiotensin-converting enzyme
d. Increasing aldosterone release
Answer: c. Inhibiting angiotensin-converting enzyme
12. Which of the following is a loop diuretic?
a. Spironolactone
b. Furosemide
c. Hydrochlorothiazide
d. Amiloride
Answer: b. Furosemide
13. Nitroglycerin acts by:
a. Calcium channel blockade
b. Alpha-1 receptor antagonism
c. Releasing nitric oxide
d. Beta receptor blockade
Answer: c. Releasing nitric oxide
14. Warfarin acts by:
a. Inhibiting thrombin
 b. Activating antithrombin III
c. Inhibiting vitamin K-dependent clotting factors
d. Blocking platelet aggregation
Answer: c. Inhibiting vitamin K-dependent clotting factors
15. Aspirin inhibits platelet aggregation by inhibiting:
a. Phospholipase A2
b. Cyclooxygenase-1 (COX-1)
c. Thrombin
d. Fibrinogen
Answer: b. Cyclooxygenase-1 (COX-1)

4. CNS Drugs

16. Which benzodiazepine has the shortest half-life?

a. Diazepam
b. Lorazepam
c. Midazolam
d. Clonazepam
Answer: c. Midazolam
17. Fluoxetine is an example of:
a. SSRI
b. SNRI
c. TCA
d. MAOI
Answer: a. SSRI
18. Which antiepileptic drug blocks sodium channels?
a. Ethosuximide
b. Valproate
c. Phenytoin
d. Phenobarbital
Answer: c. Phenytoin
19. Clozapine is used primarily for:
a. Depression
b. Schizophrenia resistant to other drugs
c. Bipolar disorder
d. Anxiety
Answer: b. Schizophrenia resistant to other drugs
20. Levodopa is combined with Carbidopa to:
a. Reduce peripheral dopamine metabolism
b. Increase dopamine levels in the periphery
c. Inhibit MAO-B
d. Reduce side effects of levodopa
Answer: a. Reduce peripheral dopamine metabolism
5. Chemotherapy

21. Penicillin acts by inhibiting:

a. DNA synthesis
b. RNA polymerase
c. Protein synthesis
d. Bacterial cell wall synthesis
Answer: d. Bacterial cell wall synthesis
22. Amphotericin B targets:
a. Ergosterol in fungal membranes
b. Peptidoglycan synthesis
c. Viral DNA polymerase
d. Mycolic acid synthesis
Answer: a. Ergosterol in fungal membranes
23. Acyclovir is most effective against:
a. Influenza
b. Herpes simplex virus
c. HIV
d. Hepatitis C
Answer: b. Herpes simplex virus
24. Methotrexate inhibits:
a. Topoisomerase II
b. Dihydrofolate reductase
c. RNA polymerase
d. DNA polymerase
Answer: b. Dihydrofolate reductase
25. Which drug is a monoclonal antibody?
a. Trastuzumab
b. Doxorubicin
c. Cisplatin
d. Tamoxifen
Answer: a. Trastuzumab

Case 1: Hypertension

1. A 55-year-old male with essential hypertension is prescribed Enalapril. Which of the

following mechanisms best explains the action of this drug?
a. Inhibition of ACE (angiotensin-converting enzyme)
b. Blockade of beta-adrenergic receptors
c. Inhibition of aldosterone secretion
d. Blockade of calcium channels

Answer: a. Inhibition of ACE

2. A patient is started on Enalapril. Which of the following side effects is most commonly
associated with this class of drugs?
a. Hyperkalemia
b. Hypokalemia
c. Constipation
d. Insomnia

Answer: a. Hyperkalemia

3. A 60-year-old male with hypertension and asthma is started on a medication for blood
pressure. Which drug is contraindicated in this patient?
a. Losartan
b. Amlodipine
c. Propranolol
d. Doxazosin

Answer: c. Propranolol

Case 2: Diabetes Mellitus

4. A 45-year-old woman with Type 2 diabetes is prescribed Metformin. Which of the

following is the primary action of Metformin in lowering blood sugar?
a. Increases insulin secretion
b. Increases glucose uptake by muscle and fat
c. Decreases hepatic glucose production
d. Inhibits glucagon secretion

Answer: c. Decreases hepatic glucose production

5. A diabetic patient is started on a new medication that increases insulin sensitivity and
has a risk of weight gain and edema. Which drug is most likely prescribed?
a. Sitagliptin
b. Metformin
c. Pioglitazone
d. Glimepiride

Answer: c. Pioglitazone

6. A 62-year-old diabetic patient is given insulin therapy. What is the most important
adverse effect of insulin therapy that the patient should be educated about?
a. Hyperkalemia
b. Hypoglycemia
c. Hyperglycemia
d. Weight loss
Answer: b. Hypoglycemia

Case 3: Asthma

7. A 30-year-old female with asthma is prescribed a short-acting beta-agonist. Which of the

following medications is most commonly used for immediate relief of asthma symptoms?
a. Salbutamol (Albuterol)
b. Fluticasone
c. Montelukast
d. Theophylline

Answer: a. Salbutamol (Albuterol)

8. A patient is using inhaled corticosteroids to manage asthma. Which of the following is an

important side effect of inhaled corticosteroids?
a. Oral thrush
b. Weight gain
c. Tachycardia
d. Hypoglycemia

Answer: a. Oral thrush

9. A 24-year-old female with asthma is prescribed a leukotriene receptor antagonist. Which

of the following drugs would be used?
a. Montelukast
b. Albuterol
c. Fluticasone
d. Salmeterol

Answer: a. Montelukast

Case 4: Pain Management

10. A 48-year-old male presents with moderate pain after surgery and is prescribed a drug
for pain relief. Which of the following drugs is an opioid analgesic?
a. Ibuprofen
b. Acetaminophen
c. Morphine
d. Naproxen

Answer: c. Morphine
11. A patient is prescribed Codeine for pain management. What is a significant adverse
effect of opioid use that the patient should be aware of?
a. Diarrhea
b. Constipation
c. Tachycardia
d. Insomnia

Answer: b. Constipation

12. A patient with severe osteoarthritis is prescribed a nonsteroidal anti-inflammatory drug

(NSAID). Which of the following is a common side effect of NSAIDs?
a. Hepatotoxicity
b. Gastric ulcers
c. Hyperkalemia
d. Hypoglycemia

Answer: b. Gastric ulcers

Case 5: Antibiotic Therapy

13. A 22-year-old female is diagnosed with a urinary tract infection and is prescribed
Nitrofurantoin. What is the primary mechanism of action of Nitrofurantoin?
a. Inhibits bacterial cell wall synthesis
b. Inhibits protein synthesis
c. Inhibits DNA replication
d. Inhibits folic acid synthesis

Answer: c. Inhibits DNA replication

14. A 28-year-old patient presents with an ear infection. The doctor prescribes Amoxicillin.
What is the mechanism of action of Amoxicillin?
a. Inhibits bacterial DNA gyrase
b. Inhibits bacterial cell wall synthesis
c. Binds to bacterial ribosomes
d. Inhibits folic acid metabolism

Answer: b. Inhibits bacterial cell wall synthesis

15. A 40-year-old male develops a severe allergic reaction after taking penicillin. Which of
the following is the most appropriate treatment for the reaction?
a. Diphenhydramine
b. Epinephrine
c. Prednisone
d. Aspirin
Answer: b. Epinephrine

Case 6: Sepsis and Shock

16. A 60-year-old male with septic shock is given norepinephrine. What is the primary
mechanism of action of norepinephrine in shock?
a. Vasoconstriction to increase blood pressure
b. Direct cardiac muscle stimulation
c. Inhibition of inflammatory cytokines
d. Dilates the blood vessels to improve perfusion

Answer: a. Vasoconstriction to increase blood pressure

17. A patient with septic shock is given IV fluids and vasopressors. Which class of drugs is
used to increase vascular tone in shock?
a. Inotropes
b. Vasopressors
c. Antihypertensives
d. Diuretics

Answer: b. Vasopressors

Case 7: Gastrointestinal Disorders

18. A patient is prescribed Omeprazole for gastroesophageal reflux disease (GERD). What
is the mechanism of action of Omeprazole?
a. Inhibits proton pump in gastric parietal cells
b. Increases gastric motility
c. Inhibits H2 receptors in the stomach
d. Neutralizes gastric acid

Answer: a. Inhibits proton pump in gastric parietal cells

19. A 50-year-old female presents with ulcers, and her physician prescribes an H2 receptor
antagonist. Which drug is most commonly used for this purpose?
a. Ranitidine
b. Omeprazole
c. Sucralfate
d. Misoprostol

Answer: a. Ranitidine
20. A patient with chronic constipation is prescribed a bulk-forming laxative. Which of the
following drugs would be appropriate?
a. Psyllium
b. Bisacodyl
c. Lactulose
d. Docusate

Answer: a. Psyllium

Case 8: Hyperlipidemia

21. A 40-year-old male with hyperlipidemia is prescribed Atorvastatin. What is the

mechanism of action of statins?
a. Inhibits HMG-CoA reductase
b. Inhibits cholesterol absorption
c. Increases HDL levels
d. Increases lipoprotein lipase activity

Answer: a. Inhibits HMG-CoA reductase

22. A patient on atorvastatin reports muscle pain and weakness. Which of the following is
the most likely cause?
a. Hyperkalemia
b. Myopathy
c. Hepatotoxicity
d. Dyspepsia

Answer: b. Myopathy

Case 9: Anticoagulation Therapy

23. A 70-year-old female with a history of deep vein thrombosis is prescribed Warfarin.
What is the primary mechanism of action of Warfarin?
a. Inhibition of thrombin
b. Inhibition of Vitamin K-dependent clotting factors
c. Inhibition of platelet aggregation
d. Activation of antithrombin III

Answer: b. Inhibition of Vitamin K-dependent clotting factors

24. A patient on Warfarin therapy needs surgery. Which test is most useful for monitoring
Warfarin therapy?
a. PT (Prothrombin Time)
b. APTT (Activated Partial Thromboplastin Time)
c. INR (International Normalized Ratio)
d. Platelet count

Answer: c. INR

20 Matching Pharmacology Questions

Instructions: Match each drug/condition with its corresponding description or mechanism of action.

1. Metformin
2. Furosemide
3. Aspirin
4. Albuterol
5. Propranolol
6. Warfarin
7. Atropine
8. Morphine
9. Penicillin
10. Clopidogrel
11. Diazepam
12. Ciprofloxacin
13. Methotrexate
14. Lisinopril
15. Prednisone
16. Simvastatin
17. Nitroglycerin
18. Salbutamol
19. Diphenhydramine
20. Hydrochlorothiazide

A. Inhibits bacterial cell wall synthesis.

B. Used for acute bronchospasm relief (bronchodilation).
C. Increases the risk of bleeding by inhibiting platelet aggregation.
D. Inhibits prostaglandin synthesis (COX-1 and COX-2 inhibition).
E. Increases glucose uptake and decreases hepatic glucose production.
F. Inhibits HMG-CoA reductase to lower cholesterol.
G. Acts as a vasodilator, used for angina or acute myocardial infarction.
H. Used for treating hypertension and heart failure (ACE inhibitor).
I. Used in acute opioid overdose (opioid antagonist).
J. Reduces inflammation and immune response in autoimmune diseases.
K. Blocks beta-adrenergic receptors (used for hypertension and anxiety).
L. Inhibits vitamin K-dependent clotting factors.
M. Inhibits sodium reabsorption at the distal nephron (diuretic).
N. Used for treating bacterial infections (e.g., UTI, respiratory infections).
O. Used in cancer treatment to inhibit folate synthesis (antimetabolite).
P. Used to prevent and treat nausea and allergic reactions (antihistamine).
Q. Treats severe pain by acting on opioid receptors (analgesic).
R. Reduces the activity of the immune system by inhibiting DNA synthesis.
S. Used for management of asthma, especially for long-term control.
T. Increases blood sugar and is used for managing hyperglycemia.

Answers:

1. E. Increases glucose uptake and decreases hepatic glucose production (Metformin).

2. M. Inhibits sodium reabsorption at the distal nephron (diuretic) (Furosemide).

3. D. Inhibits prostaglandin synthesis (COX-1 and COX-2 inhibition) (Aspirin).

4. B. Used for acute bronchospasm relief (bronchodilation) (Albuterol).

5. K. Blocks beta-adrenergic receptors (used for hypertension and anxiety) (Propranolol).

6. L. Inhibits vitamin K-dependent clotting factors (Warfarin).

7. I. Used in acute opioid overdose (opioid antagonist) (Atropine).

8. Q. Treats severe pain by acting on opioid receptors (analgesic) (Morphine).

9. A. Inhibits bacterial cell wall synthesis (Penicillin).

10. C. Increases the risk of bleeding by inhibiting platelet aggregation (Clopidogrel).

11. P. Used to prevent and treat nausea and allergic reactions (antihistamine) (Diphenhydramine).

12. N. Used for treating bacterial infections (e.g., UTI, respiratory infections) (Ciprofloxacin).

13. O. Used in cancer treatment to inhibit folate synthesis (antimetabolite) (Methotrexate).

14. H. Used for treating hypertension and heart failure (ACE inhibitor) (Lisinopril).

15. J. Reduces inflammation and immune response in autoimmune diseases (Prednisone).

16. F. Inhibits HMG-CoA reductase to lower cholesterol (Simvastatin).

17. G. Acts as a vasodilator, used for angina or acute myocardial infarction (Nitroglycerin).
 18. S. Used for management of asthma, especially for long-term control (Salbutamol).

19. P. Used to prevent and treat nausea and allergic reactions (antihistamine) (Diphenhydramine).

20. M. Inhibits sodium reabsorption at the distal nephron (diuretic) (Hydrochlorothiazide).

20 True/False Pharmacology Questions

1. Aspirin is a selective COX-2 inhibitor.

Answer: False (Aspirin inhibits both COX-1 and COX-2.)

2. Beta-blockers are commonly used in the treatment of arrhythmias.

Answer: True

3. Warfarin is an anticoagulant that works by inhibiting platelet aggregation.

Answer: False (Warfarin inhibits vitamin K-dependent clotting factors, not platelet aggregation.)

4. Insulin is used to increase blood glucose levels in diabetic patients.

Answer: False (Insulin decreases blood glucose levels.)

5. Morphine is classified as a non-opioid analgesic.

Answer: False (Morphine is an opioid analgesic.)

6. Omeprazole is a proton pump inhibitor used to reduce stomach acid.

Answer: True

7. Penicillin is effective against viral infections.

Answer: False (Penicillin is effective against bacterial infections.)

8. Diazepam is a benzodiazepine used for anxiety and seizure disorders.

Answer: True

9. Metformin is used for the treatment of Type 1 diabetes only.

Answer: False (Metformin is used in Type 2 diabetes.)

10. ACE inhibitors are commonly used to treat heart failure and hypertension.
Answer: True

11. Theophylline is used as a bronchodilator in asthma.

Answer: True

12. Ciprofloxacin is an antibiotic that inhibits bacterial cell wall synthesis.

Answer: False (Ciprofloxacin inhibits bacterial DNA gyrase.)

13. Hydrochlorothiazide is a loop diuretic used for managing hypertension.

Answer: False (Hydrochlorothiazide is a thiazide diuretic, not a loop diuretic.)
 14. Clopidogrel works by inhibiting thrombin activity.
Answer: False (Clopidogrel inhibits platelet aggregation by blocking ADP receptors.)

15. Statins lower cholesterol by inhibiting the enzyme HMG-CoA reductase.

Answer: True

16. Levodopa is used to treat Parkinson's disease by replenishing dopamine.

Answer: True

17. Furosemide is a potassium-sparing diuretic.

Answer: False (Furosemide is a loop diuretic and causes potassium loss.)

18. Tetracycline antibiotics should be avoided in pregnant women.

Answer: True

19. Prednisone is used for its anti-inflammatory and immunosuppressive effects.

Answer: True

20. Nitroglycerin is used to lower blood pressure by acting as a vasodilator.

Answer: True

1. Drug Classification

Understand the major classes of drugs and their subtypes:

 Antibiotics: Penicillins, cephalosporins, tetracyclines, fluoroquinolones, etc.

 Analgesics: Opioids (morphine, codeine) and non-opioids (NSAIDs, acetaminophen).
 Antihypertensives: ACE inhibitors (lisinopril), beta-blockers (metoprolol), diuretics
(hydrochlorothiazide), calcium channel blockers (amlodipine).
 Antidiabetic drugs: Insulin, sulfonylureas (glimepiride), biguanides (metformin), DPP-4
inhibitors (sitagliptin).
 Antidepressants: SSRIs (fluoxetine), SNRIs (venlafaxine), tricyclics (amitriptyline).
 Anticancer drugs: Chemotherapy agents, targeted therapies, and immunotherapies.

2. Mechanism of Action (MOA)

For each class of drugs, know the mechanism of action:

 ACE inhibitors: Block ACE, reducing Angiotensin II, leading to vasodilation and
reduced blood pressure.
 Beta-blockers: Block beta-adrenergic receptors, decreasing heart rate and blood
pressure.
 Antibiotics: Inhibit bacteria’s ability to replicate or function (e.g., beta-lactams inhibit
cell wall synthesis).
 Statins: Inhibit HMG-CoA reductase, reducing cholesterol synthesis.
3. Side Effects and Toxicities

Be familiar with common and serious side effects for major drug classes:

 Antibiotics: Rash, gastrointestinal upset, hepatotoxicity.

 NSAIDs: GI bleeding, renal impairment, increased cardiovascular risk.
 Opioids: Respiratory depression, constipation, addiction potential.
 ACE inhibitors: Cough, hyperkalemia, angioedema.

4. Drug Interactions

Learn common drug-drug interactions:

 Warfarin: Interacts with drugs that alter its metabolism (e.g., antibiotics, NSAIDs) and
vitamin K-containing foods.
 SSRIs and MAOIs: Risk of serotonin syndrome.
 CYP450 enzyme inhibitors/inducers: E.g., grapefruit juice inhibits CYP3A4, affecting
drugs like statins.

5. Pharmacokinetics

Understand the basic principles of pharmacokinetics:

 Absorption: How a drug enters the bloodstream.

 Distribution: How the drug moves throughout the body (protein binding, volume of
distribution).
 Metabolism: How the liver processes the drug (CYP450 system).
 Excretion: How the body eliminates the drug (kidneys, bile).

6. Pharmacodynamics

Know how the drug affects the body:

 Receptors: Agonists vs. antagonists.

 Dose-response curve: Relationship between drug dose and effect (e.g., therapeutic
index).
 Half-life: Time taken for plasma concentration to reduce by half.

7. Clinical Use and Indications

Know which conditions each drug is used for:

 Antihypertensives: Used for high blood pressure, heart failure, chronic kidney disease.
 Antibiotics: Used for bacterial infections, e.g., UTI, pneumonia.
 Diuretics: Used for hypertension, heart failure, edema.
8. Special Populations

Learn how drugs affect different populations:

 Pediatrics: Age-related differences in drug metabolism and dosing.

 Pregnancy: Drugs that are contraindicated (e.g., ACE inhibitors, tetracyclines).
 Elderly: Age-related changes in pharmacokinetics (e.g., slower metabolism).

9. Laboratory Monitoring

Know which lab tests are important for certain drugs:

 Warfarin: INR (International Normalized Ratio) to monitor bleeding risk.

 Lithium: Serum levels to avoid toxicity.
 Diuretics: Potassium levels, kidney function.

10. Critical Drugs and Emergencies

Be familiar with emergency drugs and how to manage common clinical situations:

 Anaphylaxis: Epinephrine.
 Cardiac arrest: Epinephrine, atropine, amiodarone.
 Sepsis: Antibiotics, fluids, vasopressors.
 Hypoglycemia: Glucose or glucagon administration.

11. Mnemonics and Study Tips

Use mnemonics to remember complex information:

 "M.O.A.T" for pharmacokinetics: Metabolism, Onset, Absorption, Time.

 "ABC" for adverse effects: Agitation, Bleeding, Constipation (for common drug side
effects).

Antibiotics:

Antibiotics are drugs used to treat bacterial infections. They target various components of the bacterial
cell to either kill the bacteria (bactericidal) or inhibit its growth (bacteriostatic).

1. Cell Wall Synthesis Inhibitors:

o Mode of Action: Inhibit the formation of the bacterial cell wall, causing the bacteria to
lyse (break apart).

o Examples:

 Penicillins (e.g., Amoxicillin, Penicillin)

  Cephalosporins (e.g., Ceftriaxone)

 Vancomycin

2. Protein Synthesis Inhibitors:

o Mode of Action: Bind to bacterial ribosomes, inhibiting protein synthesis.

o Examples:

 Macrolides (e.g., Azithromycin, Erythromycin)

 Tetracyclines (e.g., Doxycycline)

 Aminoglycosides (e.g., Gentamicin)

 Chloramphenicol

3. DNA/RNA Synthesis Inhibitors:

o Mode of Action: Inhibit the enzymes involved in DNA or RNA synthesis, thus preventing
bacterial replication.

o Examples:

 Fluoroquinolones (e.g., Ciprofloxacin, Levofloxacin) - Inhibit DNA gyrase

(topoisomerase).

 Rifamycins (e.g., Rifampin) - Inhibit bacterial RNA polymerase.

4. Folate Synthesis Inhibitors:

o Mode of Action: Block the synthesis of folic acid, which is necessary for nucleic acid and
protein synthesis in bacteria.

o Examples:

 Sulfonamides (e.g., Sulfamethoxazole)

 Trimethoprim (often combined with sulfamethoxazole as co-trimoxazole)

5. Cell Membrane Disruptors:

o Mode of Action: Damage the bacterial cell membrane, causing leakage of cellular
contents and bacterial death.

o Examples:

 Polymyxins (e.g., Polymyxin B)

  Daptomycin

Antifungals:

Antifungals are used to treat fungal infections by targeting various parts of fungal cells, particularly cell
wall synthesis or membrane function.

1. Cell Membrane Disruptors:

o Mode of Action: Bind to ergosterol in the fungal cell membrane, causing membrane
disruption and leakage of cell contents.

o Examples:

 Amphotericin B

 Nystatin (mainly used for topical infections)

2. Ergosterol Synthesis Inhibitors:

o Mode of Action: Inhibit the synthesis of ergosterol, a critical component of the fungal
cell membrane.

o Examples:

 Azoles (e.g., Fluconazole, Itraconazole, Ketoconazole)

 Terbinafine (inhibits squalene epoxidase)

3. Cell Wall Synthesis Inhibitors:

o Mode of Action: Inhibit the synthesis of glucan in the fungal cell wall, which weakens
the cell structure.

o Examples:

 Echinocandins (e.g., Caspofungin, Micafungin)

4. DNA Synthesis Inhibitors:

o Mode of Action: Inhibit fungal DNA replication and synthesis.

o Examples:

 Flucytosine (converted inside fungal cells to 5-fluorouracil)

Antivirals:

Antivirals are drugs used to treat viral infections. They target different stages of the viral life cycle, such
as entry into host cells, replication, or assembly of new virions.

1. Nucleoside/Nucleotide Reverse Transcriptase Inhibitors (NRTIs):

o Mode of Action: Inhibit the reverse transcription of viral RNA into DNA, a critical step in
the replication of retroviruses like HIV.

o Examples:

 Zidovudine (AZT)

 Lamivudine

 Tenofovir

2. Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs):

o Mode of Action: Bind to and inhibit reverse transcriptase, the enzyme that converts
viral RNA into DNA.

o Examples:

 Efavirenz

 Nevirapine

3. Protease Inhibitors:

o Mode of Action: Inhibit the viral protease enzyme, preventing the maturation of new
viral particles.

o Examples:

 Ritonavir

 Atazanavir

4. Neuraminidase Inhibitors:

o Mode of Action: Block the neuraminidase enzyme, preventing the release of new viral
particles from infected cells (commonly used for influenza).

o Examples:

 Oseltamivir (Tamiflu)
  Zanamivir

5. Integrase Inhibitors:

o Mode of Action: Block the viral integrase enzyme, preventing the integration of viral
DNA into the host cell's genome.

o Examples:

 Raltegravir

 Dolutegravir

6. Fusion Inhibitors:

o Mode of Action: Prevent viral entry into host cells by inhibiting fusion between the viral
and host cell membranes.

o Examples:

 Enfuvirtide (used in HIV)

7. Immunomodulators:

o Mode of Action: Enhance the host immune system's ability to fight off viral infections.

o Examples:

 Interferons (e.g., used in Hepatitis B and C)

8. Direct-Acting Antivirals (DAAs):

o Mode of Action: Target specific proteins involved in the replication of Hepatitis C virus
(HCV).

o Examples:

 Sofosbuvir

 Ledipasvir

Summary:

 Antibiotics target bacterial cell wall synthesis, protein synthesis, DNA/RNA synthesis, and cell
membrane integrity.
 Antifungals focus on inhibiting ergosterol synthesis, disrupting fungal cell membranes, or
inhibiting cell wall synthesis.

 Antivirals interfere with the viral replication cycle, targeting reverse transcriptase, protease,
neuraminidase, and other viral enzymes or processes.