Colchicine prevents gout flares by a mechanism that is distinct from NSAIDs. Its primary cellular target in gout is:

• A Inhibition of COX-1 and COX-2, reducing prostaglandin synthesis in synovium
• B Binding to tubulin, preventing microtubule polymerization and impairing neutrophil migration, degranulation, and NLRP3 inflammasome assembly ✓
• C Blockade of IL-1beta receptor on synoviocytes, reducing joint inflammation
• D Inhibition of phagocytosis by macrophages via actin depolymerization

Explanation

Colchicine binds to tubulin heterodimers, preventing their polymerization into microtubules. This disrupts microtubule-dependent processes in neutrophils: chemotaxis along urate crystal gradients, transendothelial migration, degranulation, and assembly of the NLRP3 inflammasome (which converts pro-IL-1beta to active IL-1beta). By impairing neutrophil function, colchicine blocks the key effector cells responsible for the acute gout flare without inhibiting prostaglandin synthesis.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.