Anticlotting drugs Flashcards
What are 4 classes of anti-platelet drugs?
1) NSAIDs
2) Platelet Gp2b/3A receptor blockers
3) ADP receptor blockers
4) PDE inhibitors
What is the anti-clotting moa of aspirin?
Non-selective COX inhibitor → inhibit TXA2 → inhibit platelet aggregation
What 3 clinical uses of aspirin as an anti-clotting drug?
1) Transient cerebral ischaemia prophylaxis
2) ↓incidence of recurrent MI
3) ↓mortality of post-MI px
What are 2 AEs of aspirin?
Bleeding (↓PGI2)
Gastric upset and ulcers (↓PGE2)
What are 2 examples of ADP receptor blockers?
Clopidogrel and Ticlopidine
What is an example of PDE inhibitor?
Dipyridamole
What are 3 examples of Gp2b/3A receptor blockers?
1) Abciximab (humanised mAb)
2) Eptifibatide (analogue of fibrinogen receptor-binding region)
3) Tirofiban (small molecule blocker)
What are 4 anti-coagulant classes?
1) Heparin derivatives
2) Coumarin derivatives (Warfarin)
3) Lipirudin/Hirudin
4) Anti-thrombin 3
LMW heparin have (better/worse) bioavailability and (longer/shorter) T1/2 compared to unfractionated heparin.
Better F
Longer T1/2
What is the moa of heparin?
Bind to Anti-thrombin 3 → conformational change → allows for binding to F2a (only unfractionated) and FXa
True or false: LMWH increases antithrombin 3’s action on both F10a and F2a.
False.
LMWH only increases for F10a not F2a (thrombin)
What are 3 clinical indications of heparin?
1) DVT, PE, AMI
2) Revascularisation (w thrombolytics)
3) Angioplasty/coronary stents (w GP2b/3a inhibitors)
4) When anticoagulation must be used in pregnancy
How is heparin administered?
IV or subcut
cannot IM → haematomas
What are 2 AEs of heparin?
1) Haemorrhage
2) Thrombocytopenia
How are haemorrhages due to heparin treated?
1) Stop heparin therapy
2) Protamine sulfate (cationic peptide → sequester heparin)
3) Vitamin K
