The US FDA have reported about the risk of seizures in patients with multiple sclerosis (MS) who are starting Ampyra (dalfampridine). The majority of seizures happened within days to weeks after starting the recommended dose and occurred in patients having no history of seizures. The FDA is updating the Ampyra drug label to clarify recommendations.
Ampyra was approved to improve walking in patients with MS. Seizures are a known side effect of Ampyra, and seizure risk increases with higher blood levels of the drug. Ampyra is eliminated from the body through the kidneys, and patients with kidney impairment may develop higher blood levels of the drug, thereby increasing their seizure risk.
For more details see the FDA Medwatch