Avoiding Fatal Colchicine Toxicity in Gout Patients

Avoiding colchicine toxicity became a priority because over 100 fatalities have resulted from taking colchicine in doses previously recommended for gout. New lower doses are much safer, easier to tolerate, and just as effective. This article also helps patients avoid toxicities from drug and food interactions and lets you know which patients may have special risks for colchicine toxicity.

Colchicine products and their old dosing were being used before FDA approval was required. Colcrys is the first colchicine to receive FDA approva. Dosing for colchicine was reviewed and changed during the approval process. Unapproved products will eventually be removed from the market.

Old Dosing Recommendations for Colchicine: Take two 0.6mg tablets when you first feel gout pain. Follow with one tablet hourly until you get relief or diarrhea. Dosing until diarrhea occurred probably inspired the old quip, "People treated with colchicine often run before they can walk."

New Dosing Recommendations for Colchicine: Follow the initial two tablets with just one tablet an hour later. Taking more colchicine is not helpful and is more apt to cause side effects. About ¼ of patients get side effects with new lower doses. About 80% had nausea, vomiting, and/or diarrhea on the higher doses.

Avoiding Colchicine Toxicity Due to Drug Interactions. Even with these lower dosing recommendations, it is important to tell your doctor and pharmacist about all other drugs you are taking. Dosage reduction of colchicine, even below the new dosing recommendation, is necessary when taken with clarithromycin (Biaxin), telithromycin, ketoconazole, itraconazole, HIV protease inhibitors, nefazadone, cyclosporine, erythromycin, and calcium channel blockers (like verapamil and diltiazem). These drugs interact with colchicine to cause potentially fatal toxicity.

Colchicine can cause muscle toxicity in patients taking cholesterol-lowering medications (statins and fenofibrate and gemfibrozil). Muscle toxicity can occur when taking cyclosporine or digoxin with colchicine.

Other Ways of Avoiding Colchicine Toxicity. Patients on colchicine should avoid eating grapefruit or drinking grapefruit juice.

Colchicine toxicity is more likely in patients with liver or kidney problems. If these patients receive the drug at all, the dose should be adjusted downward.

Summary

Colchicine used to be dosed every hour until diarrhea occurred. That dose has caused fatal colchicine toxicity. During FDA approval of Colcrys, dosing was reviewed and found to be too high. A lower dose is equally effective but less toxic. Colchicine dose should be reduced even below the new recommendations in patients taking drugs which are known to interact with it. Half of the reported deaths resulted from a drug interaction with Biaxin. Patients with liver or kidney problems should have downward dose adjustments or avoid colchicine altogether. Lower dosing and heeding the other cautions outlined in this article should help prevent serious or fatal colchicine toxicity.

DISCLAIMER: This article is provided for information only. This information is not a substitute for professional medical care by a qualified doctor or other health care professional. I am not responsible or liable, directly or indirectly, for any form of damages whatsoever resulting from the use (or misuse) of information contained in or implied by the information. This information is in no way intended as a recommendation of any drug therapy and is not intended as a diagnosis of any problem you may have.

Sources:

No author given. The Most Misused Gout Drug: Colchicine. Beatinggout.com.
No author given. Information for Healthcare Professionals: New Safety Information for Colchicine (marketed as Colcrys). Fda.gov.
No author given. New Safety Information for Colchicine and the Approval of Colcrys. Pharmacists Letter/Prescriber's Letter 2009:25(9):250902.