Key Drug Interactions

Question 1

Statin + fusidic acid

Answer 1

Increased risk of rhabdomyolysis

Question 2

Statin + ezetimibe

Answer 2

Increased risk of rhabdomyolysis

Question 3

Statin + macrolide

Answer 3

Increased risk of rhabdomyolysis

Question 4

Statin + fenofibrate/nicotinic acid

Answer 4

Increased risk of rhabdomyolysis

Question 5

Lercanidipine + macrolide

Answer 5

Contraindicated- due to markedly increased exposure to lercanidipine (BP reduced too much)

Question 6

Warfarin + metronidazole

Answer 6

Increased anticoagulant effect of warfarin

Question 7

Warfarin + rifampicin

Answer 7

Increased metabolism of warfarin, thus reduced anticoagulant effect

Question 8

Warfarin + macrolide

Answer 8

Increased risk of serious haemorrhage and significant elevation in INR

Question 9

Warfarin + quinolones

Answer 9

Increased risk of serious haemorrhage and significant elevation in INR

Question 10

ACEi + spironolactone

Answer 10

Increased risk of hyperkalaemia

Question 11

ACEi + NSAID

Answer 11

Increased risk of renal damage

Question 12

ACEi + K+ sparing diuretic

Answer 12

Increased risk of hyperkalaemia

Question 13

Amlodipine + simvastatin

Answer 13

Increased exposure to simvastatin

Question 14

Amiodarone + QT prolonging drugs

Answer 14

Risk of QT prolongation

Question 15

Amiodarone + digoxin

Answer 15

Increased exposure to digoxin

Question 16

Amiodarone + simvastatin

Answer 16

Increased exposure to simvastatin

Question 17

Which drugs interact with digoxin, increasing serum digoxin?

Answer 17

• P-glycoprotein transport inhibitors e.g. clarithromycin, erythromycin, ritonavir and verapamil
• Amiodarone
• Verapamil
• Macrolides
• Azole antifungals
• Cyclosporins