Master Pharmacology
for FMGE

What the FMGE Tests in Pharmacology

The FMGE Pharmacology paper tests your ability to apply drug knowledge to clinical scenarios, not just recall mechanisms. You must identify the correct first-line therapy for common conditions (e.g., hypertension, diabetes, asthma, infections), recognise adverse drug reactions (e.g., Stevens-Johnson syndrome, ototoxicity), and interpret prescription errors. Questions often present a patient with comorbidities (e.g., renal impairment, pregnancy) and ask for the safest or most appropriate drug. Antimicrobial selection based on organism susceptibility and site of infection is heavily emphasised. You will also be tested on pharmacokinetic principles (e.g., loading dose calculations, drug interactions with CYP450), antidotes (e.g., naloxone for opioids, N-acetylcysteine for paracetamol), and management of poisoning. Knowledge of WHO Essential Medicines List and standard treatment guidelines (e.g., for tuberculosis, malaria, HIV) is expected. Do not memorise trivial details; focus on clinical decision-making and drug safety.

High-Yield Concepts

• Antihypertensives in special populations: First-line for uncomplicated hypertension: ACE inhibitors (e.g., ramipril) or ARBs (e.g., losartan), but avoid in pregnancy (use labetalol or nifedipine). In diabetic nephropathy, ACE inhibitors are preferred. For resistant hypertension, add spironolactone if potassium normal. Target BP <140/90 mmHg; <130/80 mmHg if CKD or diabetes.
• Antimicrobial stewardship: MRSA and ESBL: For MRSA skin infections: vancomycin (trough 15-20 mcg/mL) or daptomycin (avoid in pneumonia). For ESBL-producing organisms: carbapenems (e.g., meropenem) are first-line. For uncomplicated UTI with ESBL: nitrofurantoin or fosfomycin trometamol. Always check local antibiogram.
• Insulin regimens and hypoglycaemia management: Basal-bolus insulin: long-acting (e.g., glargine) once daily + rapid-acting (e.g., lispro) before meals. For diabetic ketoacidosis: IV insulin infusion (0.1 U/kg/hr) with dextrose when glucose <250 mg/dL. Hypoglycaemia (<70 mg/dL): oral glucose (15 g) or IM glucagon if unconscious. Avoid beta-blockers in hypoglycaemia unawareness.
• Anticoagulants and reversal: Warfarin reversal: vitamin K (IV for INR >9 with bleeding) or fresh frozen plasma (for life-threatening bleed). DOACs (e.g., rivaroxaban): reversal with andexanet alfa. Heparin: protamine sulfate (1 mg per 100 U heparin). LMWH (e.g., enoxaparin) reversal: protamine partially effective. Monitor aPTT for heparin, anti-Xa for LMWH.
• Treatment of status epilepticus: First-line: IV lorazepam (0.1 mg/kg) or IV diazepam (0.15-0.2 mg/kg). If no IV access: IM midazolam (10 mg for >40 kg). Second-line: IV phenytoin (20 mg/kg loading) or IV levetiracetam (60 mg/kg). Refractory: IV propofol or midazolam infusion with EEG monitoring. Correct hypoglycaemia and electrolytes.
• Asthma stepwise management (GINA guidelines): Step 1: as-needed low-dose ICS-formoterol (e.g., budesonide/formoterol). Step 2: low-dose ICS maintenance plus as-needed formoterol. Step 3: low-dose ICS-LABA (e.g., fluticasone/salmeterol). Step 4: medium-dose ICS-LABA. Step 5: add tiotropium or biologics (e.g., omalizumab for allergic asthma). Avoid long-acting beta-agonists (LABA) without ICS.
• Antidotes for common poisonings: Paracetamol overdose: N-acetylcysteine (IV, 300 mg/kg over 21 hours) if serum level above treatment line (Rumack-Matthew nomogram). Opioid overdose: naloxone (0.4-2 mg IV, repeat q2-3 min). Organophosphate poisoning: atropine (2 mg IV q5-10 min until dry secretions) + pralidoxime (30 mg/kg IV loading). Benzodiazepine overdose: flumazenil (0.2 mg IV, max 3 mg), but avoid in mixed overdose with tricyclics.
• Drug interactions with CYP450 and P-glycoprotein: CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin, grapefruit juice) increase levels of simvastatin, midazolam, and tacrolimus (risk of rhabdomyolysis, sedation, nephrotoxicity). CYP3A4 inducers (e.g., rifampicin, phenytoin, St John's Wort) reduce efficacy of oral contraceptives and warfarin. P-glycoprotein inhibitors (e.g., verapamil, amiodarone) increase digoxin levels—monitor serum digoxin.

Common Traps in Pharmacology Questions

• Confusing loading dose with maintenance dose: loading dose is based on volume of distribution, not clearance.
• Assuming all beta-blockers are contraindicated in asthma: cardioselective beta-1 blockers (e.g., bisoprolol) can be used cautiously if necessary, but non-selective ones (e.g., propranolol) are contraindicated.
• Forgetting to adjust doses in renal impairment: e.g., gabapentin, enoxaparin, and many antibiotics (e.g., gentamicin) require dose reduction; avoid nitrofurantoin if eGFR <30 mL/min.
• Using flumazenil routinely for benzodiazepine overdose: it can precipitate seizures in patients with chronic benzodiazepine use or co-ingestion of tricyclic antidepressants.
• Mixing up antibiotic coverage: e.g., ceftriaxone covers Neisseria gonorrhoeae but not MRSA; vancomycin covers MRSA but not Gram-negative bacilli.
• Thinking that all statins are equally potent: rosuvastatin and atorvastatin are high-intensity; simvastatin 40 mg is moderate; pravastatin is low-intensity and preferred in liver impairment.

How to Revise Pharmacology for the FMGE

Prioritise first-line drug choices for common conditions (hypertension, diabetes, asthma, infections) and management of adverse effects. Questions often present a patient with a comorbidity (e.g., renal failure, pregnancy, liver disease) and ask for the safest drug. Practice interpreting drug level nomograms (e.g., paracetamol, lithium, digoxin) and calculating doses based on weight or creatinine clearance. Focus on antimicrobial selection by site and organism (e.g., meningitis: ceftriaxone + vancomycin; pneumonia: amoxicillin or doxycycline). Memorise key antidotes and reversal agents. Traps often involve drug interactions (e.g., warfarin + rifampicin) or contraindications (e.g., metformin in eGFR <30). Use mnemonics for side-effect profiles (e.g., 'ABCDE' for aminoglycosides: Ataxia, Balance, Cochlear, Deafness, Equilibrium). Revise the WHO Essential Medicines List for antimalarials, anti-TB drugs, and antiretrovirals.

Practise it: MedLumen has 50 Pharmacology questions for the FMGE, each with a full explanation and references.