Colchicine is used for acute gout flares. Its primary mechanism of action is:

• A Binding to tubulin and inhibiting microtubule polymerization, impairing neutrophil migration and inflammasome activation ✓
• B Inhibition of xanthine oxidase, reducing uric acid synthesis
• C Competitive inhibition of urate transporters in the renal tubule, promoting uricosuria
• D Selective COX-2 inhibition in synovial tissue

Explanation

Colchicine binds tubulin heterodimers with high affinity, preventing microtubule assembly; this disrupts neutrophil cytoskeletal function, impairing chemotaxis toward urate crystals, phagocytosis, and superoxide generation. Additionally, it inhibits NLRP3 inflammasome assembly and interleukin-1β secretion, blocking the key inflammatory cascade in acute gout. It does not lower uric acid levels and has no effect on urate transport or COX enzymes.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.