Haematological (Heparins - Low Molecular Weight Heparin)

Question 1

Examples of drug (Heparins - Low Molecular Weight Heparin)

Answer 1

• Low Molecular Weight Heparin

Question 2

Mechanism of action (Heparins - Low Molecular Weight Heparin)

Answer 2

• Enhances activity of antithrombin III.
• Antithrombin III inhibits thrombin.
• Heparins also inhibit multiple other factors of the coagulation cascade.
• This produces its anticoagulant effect.

Question 3

Indications (Heparins - Low Molecular Weight Heparin)

Answer 3

• Treatment and prophylaxis of thromboembolic diseases, including induction of vitamin K antagonists.
• Renal dialysis (haemodialysis)
• ACS treatment

Question 4

Side effects (Heparins - Low Molecular Weight Heparin)

Answer 4

• Bleeding (Major haemorrhage risk can be as high as 3.5%)
• Heparin-induced thrombocytopenia (Less risk than unfractionated heparin)
• Osteoporosis (Less risk than unfractionated heparin)

Question 5

Important pharmacokinetics/pharmacodynamics (Heparins - Low Molecular Weight Heparin)

Answer 5

• Subcutaneous injection
• More predictable dose-response relationship than Unfractionated Heparin.
• 2-4 times longer plasma half-life than Unfractionated Heparin
• Clearance is mostly via a renal pathway, thus the half-life can be prolonged in patients with renal failure, so dose adjustment may be needed.
• Regular coagulation monitoring is not required.
• Less readily reversed with protamine, than Unfractionated Heparin.

Question 6

Patient information (Heparins - Low Molecular Weight Heparin)

Answer 6

• Risk of bleeding
• Requires injection
• Will need blood testing in prolonged therapy (Full Blood Count, to monitor for thrombocytopenia).