US FDA says epilepsy drug can cause blood disorder

An epilepsy drug used to treat partial seizures in adults can cause excessive acidity of the blood in some patients, the U.S. Food and Drug Administration said on Monday.

Zonisamide is sold by a number of generic drugmakers as well as under the brand Zonegran by Eisai Co Ltd. Generic makers include Teva Pharmaceutical Industries Ltd, Mylan Inc, Ovaritis GA’s Sandoz unit and Watson Pharmaceuticals Inc, according to the FDA’s web site.

The condition, known as metabolic acidosis, can include a variety of symptoms such as fatigue, anorexia, irregular heartbeat or stupor, the FDA said in a statement.

Over time, the condition can cause kidney and bone problems, the FDA said. The condition seems to be worse and more frequent in younger patients, it added.

Doctors should test patients’ blood before using zonisamide and then periodically during treatment even if they show no symptoms, the FDA said.

The FDA posted the statement on its web site at http://www. fda.gov/cder/drug/InfoSheets/HCP/zonisamideHCP.htm

WASHINGTON (Reuters)