Antiplatelet

Question 1

What class of drug is Clopidogrel?

Answer 1

Antiplatelet drug

Question 2

What are the indications for Clopidogrel?

Answer 2

Long term therapy (if Aspirin is contraindicated) for ischaemic stroke and TIA
NSTEMI- aspirin plus
PCI prasugrel unless bleeding risk is very high (ticagrelor or clopidogrel)
No PCI Then ticagrelor unless bleeding risk is very high (clopidogrel)

Question 3

What is the mechanism of action of Clopidogrel?

Answer 3

ADP receptor antagonist. Inhibits binding of ADP to P2Y12 receptor. Inhibits activation of GPIIB/IIIa receptors.

Question 4

What are the adverse effects of Clopidogrel?

Answer 4

GI bleeding, dyspepsia and diarrhoea

Question 5

What are the drug-drug interactions of Clopidogrel

Answer 5

Clopidogrel needs CYP2C19 for activation. Thus any drug that interferes with this cytochrome. Omeprazole, ciprofloxacin (quinolone antibiotics) and erythromyocin (macrolide)

Question 6

How can you remember Clopidogrel?

Answer 6

Question 7

What class of drug is Aspirin?

Answer 7

Cyclo-oxygenase inhibitor

Question 8

What are the common indications of Aspirin?

Answer 8

• Atrial fibrillation patients past stroke
• Secondary prevention of stroke and TIA
• Secondary prevention of acute coronary syndromes
• Often co prescribed with other antiplatelet agents

Question 9

What is the mechanism of action of Aspirin?

Answer 9

Aspirin irreversibly binds to COX-1 and reduces the production of TXA2 (thromboxane A2) which reduces platelet aggregation

Question 10

What are the adverse effects of Aspirin?

Answer 10

• Gastrointestinal irritation
• Peptic ulcer- GI bleeding
• Haemorrhage

Question 11

What are the drug-drug interactions of Aspirin?

Answer 11

Other antiplatelet and anticoagulants

Question 12

What are the doses for Aspirin?

Answer 12

Loading dose is 300mg used in acute coronary syndromes
Action at low non-analgesic doses is 75mg