PLAB 1 Pharmacology and Therapeutics

Question 1

A patient is started on warfarin for atrial fibrillation. According to NICE guidelines, what is the target INR range for non-valvular AF?

Accepted Answer

2.0-3.0

Answer

1.0-1.5

Answer

3.0-4.0

Answer

4.0-5.0

Question 2

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?

Accepted Answer

Aspirin 300 mg plus a P2Y12 inhibitor (e.g., ticagrelor or clopidogrel)

Answer

Aspirin alone

Answer

Clopidogrel alone

Answer

Warfarin and aspirin

Question 3

A patient on metformin 1g BD develops an eGFR of 28 mL/min. According to BNF guidelines, what should be done with the metformin?

Accepted Answer

Stop metformin — it is contraindicated when eGFR falls below 30 mL/min due to the risk of lactic acidosis

Answer

Continue at the same dose — renal function does not affect metformin dosing

Answer

Double the dose to compensate for reduced efficacy

Answer

Switch to insulin only if HbA1c rises above 80 mmol/mol

Question 4

A GP is prescribing ramipril for a patient with newly diagnosed hypertension. What monitoring is required after starting an ACE inhibitor?

Accepted Answer

Renal function and electrolytes should be checked before starting and 1-2 weeks after initiation or dose change

Answer

No monitoring is required

Answer

Only blood pressure monitoring is needed

Answer

Liver function tests should be checked monthly

Question 5

A patient with epilepsy controlled on sodium valproate discovers she is pregnant. What is the most important concern regarding sodium valproate in pregnancy?

Accepted 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

Answer

Sodium valproate has no effect on pregnancy outcomes

Answer

Sodium valproate only causes minor cosmetic abnormalities

Answer

Sodium valproate is safe in the first trimester but should be stopped in the third

Question 6

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?

Accepted Answer

Stop simvastatin immediately — the elevated CK indicates rhabdomyolysis/myopathy, a serious adverse effect of statins

Answer

Continue simvastatin and reassure the patient

Answer

Increase the dose of simvastatin

Answer

Add a fibrate to the simvastatin