FDA Takes Action on Injectable Colchicine

FDA is taking action against companies marketing injectable colchicine, which is an unapproved form of the drug. Colchicine is an anti-inflammatory used in the treatment of gout. Colchicine tablets, which are less hazardous, are not affected by FDA's action at this time.

The injectable form of colchicine is especially hazardous because the therapeutic index, which is the margin between an effective dose and a toxic dose, is very narrow. Also, certain side effects that might alert the clinician that the dose is too high do not appear until the patient has already reached toxic levels, which adds to the problem.

Because of its toxicity and the availability of safer therapies, injectable colchicine is rarely used to treat gout anymore. But some practitioners are using this product to treat back pain. FDA believes that the risks of this treatment outweigh the benefits.

FDA is also cautioning pharmacies against compounding injectable colchicine products. Because the drug is so toxic, and because the therapeutic index is so narrow, any errors that occur during compounding can have potentially fatal consequences.

Additional Information:

FDA MedWatch Safety Alert. Injectable Colchicine (including drugs containing colchicine). February 6, 2008.
http://www.fda.gov/medwatch/safety/2008/safety08.htm#colchicine