GMS 6530 ANTICOAGULANTS & CHOLESTEROL EXAM
QUESTIONS AND ANSWERS WITH COMPLETE SOLUTIONS
VERIFIED
Low molecular weight heparins
Smaller forms of heparin with better bioavailability and longer half lives
Are given by SQ injection
Levels can be followed using anti-Xa activity
Contraindicated in renal disease
Examples
Enoxaparin (Lovenox)
Deltaparin (Fragmin)
Fondaparinux (Arixtra)
Unfractionated heparin
Activates antithrombin III in the plasma
Antithrombin inhibits thrombin (IIa), IXa, Xa.
Not effective orally, given s.c. or i.v.
, Has a rapid onset of action when given parenterally
Structure is a sulfated glycosaminoglycan
Used for immediate anticoagulation (for example therapy in myocardial infarction)
Other uses: venous thrombosis, pulmonary embolism, thrombosis prophylaxis
Used for first 7-10 days followed by warfarin with a 3-5 day overlap
Monitored in past by partial thromboplastin time (PTT) and now more recently by
heparin levels
Can cause Heparin Induced Thrombocytopenia (HIT)
in ~1-4% of patients → STOP heparin!! (+ direct IIa inh)
Antidote: Protamine (a basic protein) - neutralizes acidic heparin
Warfarin
Acts as an anticoagulant indirectly
Inhibits the proper synthesis of vitamin K-dependent factors (II, VII, IX and X)
Has a delayed onset action: time required to decrease the plasma levels of preformed
clotting factors
Monitored using protime (PT)
QUESTIONS AND ANSWERS WITH COMPLETE SOLUTIONS
VERIFIED
Low molecular weight heparins
Smaller forms of heparin with better bioavailability and longer half lives
Are given by SQ injection
Levels can be followed using anti-Xa activity
Contraindicated in renal disease
Examples
Enoxaparin (Lovenox)
Deltaparin (Fragmin)
Fondaparinux (Arixtra)
Unfractionated heparin
Activates antithrombin III in the plasma
Antithrombin inhibits thrombin (IIa), IXa, Xa.
Not effective orally, given s.c. or i.v.
, Has a rapid onset of action when given parenterally
Structure is a sulfated glycosaminoglycan
Used for immediate anticoagulation (for example therapy in myocardial infarction)
Other uses: venous thrombosis, pulmonary embolism, thrombosis prophylaxis
Used for first 7-10 days followed by warfarin with a 3-5 day overlap
Monitored in past by partial thromboplastin time (PTT) and now more recently by
heparin levels
Can cause Heparin Induced Thrombocytopenia (HIT)
in ~1-4% of patients → STOP heparin!! (+ direct IIa inh)
Antidote: Protamine (a basic protein) - neutralizes acidic heparin
Warfarin
Acts as an anticoagulant indirectly
Inhibits the proper synthesis of vitamin K-dependent factors (II, VII, IX and X)
Has a delayed onset action: time required to decrease the plasma levels of preformed
clotting factors
Monitored using protime (PT)
