Seizure drug lowers IQ in children.

Seizure drug lowers IQ in children

A widely used drug thought to prevent fever-induced seizures in infants and young children can lower scores on intelligence quotient tests, according to a new scientific report. The authors of the report believe doctors should stop prescribing the drug, phenobarbital, for young children.

Jacqueline R. Farwell of the University of Washington School of Medicine in Seattle and deborah G. Hirtz of the National Institute of Neurological Disorders and Stroke in Bethesda, Md., studied 217 children between 8 and 36 months of age who hadhad at least one fever-induced seizure in the past and were at high risk of having another such seizure. The researchers randomly assigned children to a treatment group that got 4 to 5 milligrams per kilogram of phenobarbital daily or to a control group getting placebo pills.

After two years of treatment, the researchers found children taking phenobarbital had a mean IQ test score 8.4 points lower than children taking the placebo. The team discontinued medication and placebo for six months and repeated the testing, finding children in the treatment group had a mean IQ 5.2 points lower than controls. In addition, the researchers found children taking phenobarbital were just as likely to suffer another fever-induced seizure as their untreated peers, indicating the drug is ineffective at preventing fever-induced seizures.

"I think [phenobarbital] should not be used for febrile seizures," Farwell says. Fever-induced seizures afflict about 3 to 4 percent of all young children. In most cases such seizures don't cause any damage, but they are frightening to parents, Hirtz says. The researchers plan to follow the children in the study to see whether differences in cognitive performance persist over time.