Pharmacology · single question
What is the therapeutic/normal INR range for a patient on warfarin therapy?
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Correct answer: D. 2.0–3.0
- A. 3.5–4.5 is SUPRATHERAPEUTIC — dangerous bleeding risk. Only used for specific high-risk mechanical valve cases.
- B. 1.0–2.0 is sub-therapeutic — 1.0 is normal (no anticoagulation).
- C. 1.5–2.0 is below the therapeutic range — insufficient anticoagulation for most indications.
- D. The NORMAL THERAPEUTIC INR range for most patients on warfarin (e.g., for DVT/PE prophylaxis, atrial fibrillation, mechanical heart valves in some cases) is 2.0–3.0. For patients with mechanical prosthetic heart valves, a higher range (2.5–3.5) may be targeted.