Trusted by 50K+ Pharmacy StudentsHigh Quality Notes, MCQs, Mock Tests & Study ResourcesGo Premium (Ads Free)
Pharmacy Freak

GPAT

Mechanism of Action of Amiodarone (Class III Antiarrhythmic)

Amiodarone MOA – Multi-class antiarrhythmic with K⁺ channel blockade

Introduction Amiodarone is a powerful Class III antiarrhythmic agent used to treat various life-threatening cardiac arrhythmias, including ventricular tachycardia, ventricular fibrillation, and atrial fibrillation. It has a complex pharmacology, affecting multiple phases of the cardiac action potential and multiple ion channels. Due to its broad antiarrhythmic profile, multi-organ toxicity, and exam relevance, amiodarone is a … Read more

Mechanism of Action of Warfarin (Vitamin K Antagonist)

Warfarin MOA – Inhibition of vitamin K-dependent clotting factors

Introduction Warfarin is a widely used oral anticoagulant that inhibits the synthesis of vitamin K-dependent clotting factors. It is commonly prescribed for atrial fibrillation, deep vein thrombosis (DVT), pulmonary embolism, and prosthetic heart valves. Due to its narrow therapeutic window, multiple drug interactions, and the need for INR monitoring, warfarin is a high-yield topic for … Read more

Mechanism of Action of Colchicine (Anti-inflammatory in Gout)

Colchicine MOA – Inhibition of microtubule polymerization in neutrophils

Introduction Colchicine is an anti-inflammatory drug primarily used in the management of acute gouty arthritis, familial Mediterranean fever, and sometimes in pericarditis. It is not an analgesic or uric acid–lowering agent, but it inhibits leukocyte activity, which is key to managing gout flare-ups. Given its unique mechanism, narrow therapeutic window, and exam relevance, colchicine is … Read more

Mechanism of Action of Clopidogrel (Antiplatelet Agent)

Clopidogrel MOA – P2Y12 Receptor Inhibition on Platelets

Introduction Clopidogrel is a widely used oral antiplatelet drug belonging to the thienopyridine class. It plays a critical role in preventing thrombotic events such as myocardial infarction (MI) and ischemic stroke, especially in patients with coronary artery disease or those undergoing percutaneous coronary intervention (PCI). This drug is essential to understand for students preparing for … Read more

Mechanism of Action of Proton Pump Inhibitors (PPIs)

Proton Pump Inhibitor MOA – H⁺/K⁺ ATPase Inhibition

Introduction Proton Pump Inhibitors (PPIs) are potent acid-suppressing drugs widely used in the treatment of gastric and duodenal ulcers, GERD, Zollinger-Ellison syndrome, and for NSAID prophylaxis. Common PPIs include omeprazole, pantoprazole, esomeprazole, and lansoprazole. Their ability to irreversibly inhibit the H⁺/K⁺ ATPase enzyme in gastric parietal cells makes them high-yield for exams like USMLE, NCLEX, … Read more

Mechanism of Action of Metronidazole (DNA-Damaging Antibiotic)

Metronidazole MOA – DNA damage via nitro radical formation

Introduction Metronidazole is a unique antibiotic and antiprotozoal agent that exerts its action by damaging DNA in anaerobic organisms. It’s a first-line treatment for anaerobic bacterial infections, Clostridium difficile, and protozoal infections like Giardiasis and Trichomoniasis. It is especially important for medical and pharmacy students in the US preparing for USMLE, NCLEX, NAPLEX, and GPAT, … Read more

Mechanism of Action of Sulfonamides (Folic Acid Synthesis Inhibitors)

Sulfonamide MOA – Folic acid synthesis inhibition via dihydropteroate synthase

Introduction Sulfonamides are synthetic bacteriostatic antibiotics that inhibit folic acid synthesis in bacteria. Because mammals obtain folate from the diet, while bacteria synthesize it de novo, sulfonamides offer selective toxicity. Commonly used sulfonamides include sulfamethoxazole, sulfadiazine, and sulfisoxazole — often combined with trimethoprim for synergistic effects. This class is important in pharmacology exams like USMLE, … Read more

Mechanism of Action of Glycopeptides (e.g., Vancomycin)

Vancomycin MOA – D-Ala-D-Ala binding and peptidoglycan inhibition

Introduction Glycopeptides, most notably vancomycin, are a class of bactericidal antibiotics that inhibit bacterial cell wall synthesis by a mechanism distinct from β-lactams. Vancomycin is a crucial agent against Gram-positive infections, especially methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile. These antibiotics are vital for USMLE, NCLEX, GPAT, and NEET-PG due to their life-saving role, narrow … Read more

Mechanism of Action of Tetracyclines (Broad-Spectrum 30S Ribosome Inhibitors)

Tetracycline MOA – 30S ribosome binding and tRNA blocking

Introduction Tetracyclines are a class of broad-spectrum bacteriostatic antibiotics that inhibit bacterial protein synthesis. Common examples include tetracycline, doxycycline, minocycline, and demeclocycline. They are effective against a wide variety of Gram-positive, Gram-negative, and atypical organisms, including Rickettsia, Chlamydia, Mycoplasma, and Borrelia. Due to their broad usage and distinct mechanism, tetracyclines are high-yield topics for USMLE, … Read more

Mechanism of Action of Aminoglycosides

Aminoglycoside MOA – 30S ribosomal subunit binding and mRNA misreading

Introduction Aminoglycosides are potent bactericidal antibiotics used mainly against aerobic Gram-negative bacilli and serious systemic infections. Common examples include gentamicin, amikacin, tobramycin, streptomycin, and neomycin. Unlike most protein synthesis inhibitors, aminoglycosides are bactericidal, not bacteriostatic. They bind to the 30S subunit of the bacterial ribosome and cause misreading of mRNA, leading to faulty protein synthesis … Read more

PRO
Ad-Free Access
$3.99 / month
  • ✓ No Interruptions
  • ✓ Faster Page Loads
  • ✓ Support Content Creators
Subscribe Now