Pharmacology and Therapeutics Flashcards
6 cards from real PLAB 1 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Pharmacology and Therapeutics flashcards as text
A patient is started on warfarin for atrial fibrillation. According to NICE guidelines, what is the target INR range for non-valvular AF?
Answer: 2.0-3.0
The target INR for warfarin in non-valvular atrial fibrillation is 2.0-3.0. A higher range (2.5-3.5) is used for mechanical heart valves. DOACs (e.g., apixaban, rivarelbaan) are now recommended first-line for non-valvular AF by NICE, as they do not require INR monitoring.
A 55-year-old man presents with an acute ST-elevation myocardial infarction (STEMI). According to NICE and UK guidelines, which combination of antiplatelet drugs should be given immediately?
Answer: Aspirin 300 mg plus a P2Y12 inhibitor (e.g., ticagrelor or clopidogrel)
UK guidelines for STEMI recommend dual antiplatelet therapy (DAPT): aspirin 300 mg loading dose plus a P2Y12 inhibitor. Ticagrelor is preferred over clopidogrel for STEMI patients undergoing primary PCI. DAPT is continued for 12 months post-MI.
A patient on metformin 1g BD develops an eGFR of 28 mL/min. According to BNF guidelines, what should be done with the metformin?
Answer: Stop metformin — it is contraindicated when eGFR falls below 30 mL/min due to the risk of lactic acidosis
Metformin should be stopped when eGFR falls below 30 mL/min/1.73m2 due to the risk of lactic acidosis from impaired renal clearance. The dose should be reviewed when eGFR falls below 45, and reduced when below 30. An alternative glucose-lowering agent should be substituted.
A GP is prescribing ramipril for a patient with newly diagnosed hypertension. What monitoring is required after starting an ACE inhibitor?
Answer: Renal function and electrolytes should be checked before starting and 1-2 weeks after initiation or dose change
ACE inhibitors can cause hyperkalaemia and deterioration of renal function, particularly in patients with renovascular disease. BNF and NICE recommend checking U&Es and eGFR before starting, 1-2 weeks after starting or dose increase, and periodically thereafter. A rise in creatinine >30% or fall in eGFR >25% requires specialist review.
A patient with epilepsy controlled on sodium valproate discovers she is pregnant. What is the most important concern regarding sodium valproate in pregnancy?
Answer: Sodium valproate is a known teratogen with a 10% risk of major congenital malformations and up to 40% risk of neurodevelopmental disorders — the Pregnancy Prevention Programme must be followed
Sodium valproate is a major teratogen associated with neural tube defects, congenital malformations (10%), and neurodevelopmental disorders including autism and reduced IQ (up to 40%). The MHRA Pregnancy Prevention Programme requires two forms of contraception and annual risk acknowledgement forms for all women of childbearing potential.
A patient on simvastatin 40 mg reports new-onset muscle pain and weakness. Blood tests show a creatine kinase (CK) level 10 times the upper limit of normal. What is the most appropriate action?
Answer: Stop simvastatin immediately — the elevated CK indicates rhabdomyolysis/myopathy, a serious adverse effect of statins
Statin-induced myopathy with CK >10x ULN is a serious adverse effect that can progress to rhabdomyolysis and acute kidney injury. The statin must be stopped immediately. After CK normalises, a different statin at a low dose (e.g., pravastatin) may be tried cautiously, or an alternative lipid-lowering agent used.