Low molecular weight heparins produce a more predictable dose-response than unfractionated heparin primarily because they:
- A Are cleared hepatically rather than renally
- B Have a shorter half-life
- C Bind plasma proteins less avidly ✓
- D Do not bind antithrombin
Correct answer: C. Bind plasma proteins less avidly
Explanation
UFH binds variably to plasma proteins, endothelial cells and macrophages, producing unpredictable bioavailability and requiring aPTT monitoring. LMWH chains bind these non-specific sites far less, giving dose-independent clearance and predictable pharmacokinetics, so routine monitoring is unnecessary except in pregnancy, obesity and renal failure. LMWH has a longer half-life than UFH and is cleared renally, eliminating options B and A.
Reference: Katzung's Basic and Clinical Pharmacology, 16th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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