Carbamazepine-induced dystonia in an adolescent.

Dystonia is sustained muscle contraction, which may be primary or secondary to other causes. Drugs comprise one of the most important causes for the secondary dystonia, the usual mechanism being a dopaminergic blockade. There are very few reports describing dystonia resulting from carbamazepine (CBZ) administration. In this case report, a 16-year-old male with mental retardation and seizure disorder developed dystonia at therapeutic blood levels of CBZ.