How does colchicine work?

[zenjudo]

Hi all,

Just wana find out how colchicine for gout actually work?

Is it more a antiinflammatory or antihyperuricaemic drug?

which part of the renal tubule & structure does it work on?

cheers
zenjudo

[pharmd06]

colchicine shows some week anti-inflammatory effects and NO analgesic activity. it has no effect on uric acid secretion, levels, solubility etc.

colchicine's actions are not fully understood. it appears to reduce the inflammatory response that is caused by uric acid crystals that deposit in joints.

m

[tyler]

Hey... I just took an MCAT (medical school entry exam) that had questions about how colchicine works, and in doing some research of my own, I came across your question.

In gout, uric acid crystals are deposited in the joints. Immune cells called leukocytes try to engulf the uric acid crystals, which they recognize as foreign. The leukocytes then become hyperactivated, and they release inflammatory agents that cause the characteristic joint damage (and pain) associated with gout.

In order for the phagocytosis to occur, the leukocyte cell has to drastically change its shape to be able to engulf the uric acid crystals. Cytoskeletal elements called microtubules must dissemble and reorganize to allow the leukocytes to do this. Colchicine inhibits this reorganization of the microtubules, and thus prevents phagocytosis of the uric acid crystals by leukocytes.

To sum it up...

Colchicine = no microtubule reorginization = no phagocytic immune response to uric acid crystals = no inflammatory agents released in the joints = no joint pain

Note that colchicine only relieves pain, and does not actually CURE gout.