Colchicine is a plant alkaloid, which is effective in treatment of gout attack and/or chronic gout synovitis. Colchicine exerts anti-inflammatory effects by inhibiting chemotaxis of polymorphonuclear leukocytes, and diminishing phagocytosis. The exact mechanism of action of colchicine in gout is unknown, but colchicine exerts some of its effect by reducing the inflammatory response to the deposited crystals and by inhibiting migration of granulocytes. It is suggested, that colchicine penetrates inflammatory cells and binds tubulin molecules of the microtubular system. There it has a direct inhibitory action on the microtubules so the inflammatory cells lose their ability to respond. Colchicine is the drug of first choice to treat acute gout.
Toxicity is low when it is used in high doses for a short period. Maximal 6 mg colchicine per day is recommended to treat acute gout, while the duration of this (high dosage) treatment should not be longer than a week. To prevent acute gout attacks, a low daily dose of 0,5 mg is prescribed if prophylaxis with allopurinol or uricosurics is not possible. The most frequent side effects (when used in high doses) are nausea and diarrhea. Other known side effects are bone marrow suppression, renal failure, and alopecia.
What is NOT true about colchicine?
Extra info: Colchicine has the same mechanism of action as antimitotics, by binding tubulin in the microtubules (and thus not DNA). It is first choice for acute gout. Colchicine is partly metabolised in the liver and eliminated via bile and faeces.