The only US manufacturer of cisapride announced March 23 it will stop marketing the approved human-labeled drug July 14 of this year.
The announcement has left some veterinarians wondering what they will now use to treat megacolon in cats, short of colectomy.
The company took the voluntary action because, as of Dec 31, 1999, use of the drug has been associated with 341 reports of heart rhythm abnormalities in human patients, including 80 reports of death. Most of these adverse events occurred in patients who were taking other medications or were suffering from underlying conditions known to increase risk of cardiac arrhythmia associated with cisapride. After July 14, the company plans to continue providing limited access, for human patients who meet specific clinical eligibility criteria.
The drug has found an important niche in companion animal medicine, greatly reducing the number of subtotal colectomy procedures necessary to manage megacolon in cats.
The AVMA is working with the company to explore the possibility of continued drug availability to veterinarians for their patients.