Abstract
Data is presented on 12 patients in whom phenobarbital, when used as an anticonvulsant medication, either precipitated hyperactivity or permanently exacerbated existing hyperactivity. Discontinuation of the medication resulted in a decrease in hyperactivity in all patients. None of the patients returned to a pre-drug level of activity. The effect of phenobarbital on the reticular system is discussed. It is important for clinicians to carefully consider the potential side-effects of the use of phenobarbital in children in whom overactivity is a problem. Ascertaining whether hyperactivity has been caused or exacerbated by exposure to phenobarbital may be important in the differential diagnosis of hyperactivity.
