Haem Therapeutics

Question 0

What is the mechanism of aspirin? (1)

Answer 0

Irreversible inhibitor of cyclo-oxygenase enzyme, causing reduction in thromboxane A2 (stimulator of platelet aggregation).

Question 1

Name 2 side effects of iron supplements. (2)

Answer 1

Constipation
Diarrhoea
Nausea
Epigastric pain

Question 2

What is the mechanism of action of clopidogrel? (2)

Answer 2

Prodrug, activated by cyp450.
Inhibits binding of ADP to platelet receptors and thus inhibits activation of the GpIIb/IIIa complex and platelet activation.

Question 3

What is the mechanism of dipyridamole? (1)

Answer 3

Inhibits phosphodiesterase- mediated breakdown of cAMP, leading to impaired platelet activation.

Question 4

What is the mechanism of action for LMWH? (2)

Answer 4

Binds to and activates antithrombin.

Causing inactivation of thrombin, and other clotting proteases, especially factor Xa

Question 5

How is unfractionated heparin monitored? (1)

Answer 5

APTT

Question 6

Name 2 side effects of LMWH. (2)

Answer 6

Haemorrhage
Thrombocytopenia : immune mediated developing after 6-10 days
Hyperkalaemia : due to aldosterone secretion
Osteoporosis : in prolonged use