New research involving the use of the epilepsy medication Zonegran for weight loss has shown promising results, but raises concerns about a number of potentially severe side effects seen.
Zonegran (zonisamide) is an anticonvulsant that is primarily used to treat different types of seizures in epileptics. However, a new study published this month in the Archives of Internal Medicine examined the effectiveness of Zonegran when used to treat obese adults hoping to achieve a reduction in weight.
Researchers found that participants were affected by numerous side effects of Zonegran, which caused several to drop out during the course of the weight loss study.
The randomized double-blind placebo-controlled one year trial was conducted out of Duke university Medical center in North Carolina. It followed 225 obese participants offering a third of the group a placebo, another third a 200mg dosage of Zonegran (zonisamide) and the final third a 400mg dosage of the drug.
In addition to giving participants a placebo or Zonegran, the study also provided assistance with diet and lifestyle by providing counseling with a dietician. The results of the study found the 400 mg dosage of Zonegran to be moderately effective for weight loss, while the placebo and 200 mg dosage groups achieved similar weight loss results.
The high dosage group lost an average of 16 pounds over the course of one year, but also experienced the highest incidence of major side effects. Participants reported gastrointestinal and nervous system related problems, psychiatric issues, impaired memory, nausea, vomiting, anxiety, depression, and infections. An average of six participants in each group dropped out of the trial citing adverse effects as the reason.
Currently the medication is only approved by the FDA for seizures, but can be prescribed off-label for other uses. The label warns that Zonegran side effects can result in severe skin rashes, suicidal thoughts, and problems with memory and thinking.
Dr. Kishore M. Gadde, lead researcher of the trial, holds patents for the drug zonisamide as a treatment for obesity and is also a stake holder in a company that is developing a weight loss drug which contains the patented zonisamide.