Tiagabine in the management of postencephalitic epilepsy and impulse control disorder

Rationale. Anticonvulsants are used as primary or adjunctive agents in the treatment of psychiatric disorders. γ-Aminobutyric acid (GABA) ergic modulation has been shown to be important in impulsive aggression. We investigated the treatment of impulse control disorders with aggressive features in two patients with post-encephalitic epilepsy using the anticonvulsant tiagabine, a novel GABA reuptake inhibitor. Methods. The cases of two patients who were previously treated with other anticonvulsants, had uncontrolled behaviors with intractable seizures and were placed on adjunctive tiagabine with control of both psychiatric and neurologic symptoms, were analyzed. Results. In case 1, 12 mg adjunctive tiagabine daily resulted in behavioral improvement that further improved with increased titration; however, when tiagabine was discontinued, abrupt behavioral decompensation occurred. In case 2, adjunctive tiagabine resulted in both seizure control and marked diminution of disinhibited behaviors with aggressive outbursts; however, when tiagabine was titrated from 20 mg daily to 24 mg daily increased irritability was noted that resolved with tiagabine reduction to 20 mg daily. Conclusion. In two cases, adjunctive tiagabine was effective in the management of both epilepsy and severe impulse control disorder. Optimal dosing to maximize anticonvulsant and psychotropic effects needs to be established. Further studies using tiagabine in the treatment of impulse control disorders are indicated.