Question: A 48-year-old man with chronic gout experiences recurrent attacks despite allopurinol therapy. Which drug inhibits uric acid reabsorption in the proximal tubules? Answer: Probenecid Explanation: Probenecid inhibits the reabsorption of uric acid in the proximal tubules, increasing its excretion.
Question: A 6-month-old infant with a TSC1 gene mutation presents with infantile spasms. What is the drug of choice? Answer: Vigabatrin Explanation: Vigabatrin increases GABA levels by inhibiting GABA transaminase, effectively treating infantile spasms associated with tuberous sclerosis.
Question: Calculate the maintenance dose for a drug with 100% oral bioavailability, target concentration of 5 mg/L, clearance of 10 L/hr, dosed every 6 hours. Answer: 300 mg Explanation: Maintenance dose = Clearance × Target Concentration × Dosing Interval = 10 L/hr × 5 mg/L × 6 hr = 300 mg.
Question: A patient on risperidone develops resting tremors and rigidity. Which drug is appropriate for management? Answer: Benzhexol Explanation: Benzhexol, an anticholinergic, is effective in treating drug-induced Parkinsonism symptoms.
Question: A 72-year-old female on digoxin presents with nausea, visual disturbances, and bradycardia. Which drug should be avoided in treatment? Answer: Nifedipine Explanation: Nifedipine can exacerbate bradycardia and is contraindicated in digoxin toxicity.
Question: A patient on amantadine for Parkinson's disease develops skin discolouration. What is the likely cause? Answer: Amantadine-induced livedo reticularis Explanation: Amantadine can cause a mottled skin discolouration known as livedo reticularis.
Quick Revision Tips – Focus on high-yield topics like CNS pharmacology, cardiovascular drugs, and antimicrobials. – Practice image-based questions and pharmacokinetics calculations. – Regularly review previous year's questions to identify patterns.