Risks of Medications For People With CMT Questioned

Worsening of Charcot-Marie-Tooth (CMT) disease as a result of medication use may not be as worrisome as popular belief has portrayed it, say investigators who recently culled data from medical literature and from 209 people in the CMT North American Database, an MDA-funded registry.

Louis Weimer of Columbia University and David Podwall of Albert Einstein College of Medicine, both in New York, found the only drug with certain and potentially severe adverse consequences, even after a single dose, was vincristine, an anticancer drug.

Other drugs for which suspicions have been raised and for which prudence is suggested are those used to treat HIV/AIDS; the antibiotics metronidazole and nitrofurantoin; phenytoin, used to treat seizures; statins, used to lower cholesterol; the antidepressant sertraline, although not others in the same SSRI class of drugs; and nitrous oxide anesthesia, commonly used in dentistry.

“As with any treatment,” the investigators write in the March 15 issue of the Journal of the Neurological Sciences, “the risk of neuropathy exacerbation must be weighed against expected treatment benefits and available equivalent, alternative treatments.”

They say alternatives to the suspect medications are available in almost all instances; and when they aren’t, the suspect drugs can be used with caution and monitoring.

In general, they note, there’s “considerable disparity between the perceived risk of potentially neurotoxic medications and the number of reports in the literature, other than for vincristine.”

Michael Shy, a neurologist at Wayne State University, where he co-directs an MDA clinic and is an MDA research grantee, calls the recent paper “important for CMT patient management, since it provides the first in-depth evaluation of medications that might potentially exacerbate CMT.

“The fact that most medications have not adversely affected any form of CMT is good news for patients and emphasizes the need for data rather than theoretical concerns in management decisions involving patients.

“These results also emphasize the importance of patient registries, such as the CMT North American Database, without which much of this information could not have been obtained.”