Probenecid and colchicine contains probenecid, which is a uricosuric agent, and colchicine, which has antigout activity, the mechanism of which is unknown.

Probenecid is the generic name for 4-[(dipropylamino) sulfonyl] benzoic acid. The structural formula is represented below:

C₁₃H₁₉NO₄S....................M.W. 285.36

Probenecid is a white or nearly white, fine, crystalline powder. It is soluble in dilute alkali, in alcohol, in chloroform, and in acetone; it is practically insoluble in water and in dilute acids.

Colchicine is an alkaloid obtained from various species of Colchicum. The chemical name for colchicine is (S)-N-(5,6,7,9-tetrahydro-1,2,3,10-tetramethoxy-9-oxobenzo[α]heptalen-7-yl) acetamide. The structural formula is represented below:

C₂₂H₂₅NO₆.................................M.W. 399.44

Colchicine consists of pale yellow scales or powder; it darkens on exposure to light. Colchicine is soluble in water, freely soluble in alcohol and in chloroform, and slightly soluble in ether. Each tablet for oral administration contains 500 mg of probenecid and 0.5 mg of colchicine.

Each tablet also contains the following inactive ingredients: colloidal silicon dioxide, magnesium stearate, microcrystalline cellulose, sodium lauryl sulfate and sodium starch glycolate.

Last reviewed on RxList: 9/29/2008
This monograph has been modified to include the generic and brand name in many instances.