Search

Very few controlled clinical trials have been assessing the interaction of antipsychotics and antiepileptics. However, schizophrenic patients frequently receive a combination therapy consisting of haloperidol and carbamazepine. The data for this treatment strategy are contradictory and may depend on the initial plasma concentration of the antipsychotic. There is convincing evidence that after addition of carbamazepine the plasma concentration of neuroleptics drops due to hepatic enzyme induction. In this study, we treated 18 schizophrenic patients either with haloperidol alone or in combination with carbamazepine. The use of carbamazepine was associated with a dramatic fall in haloperidol plasma levels and a worse clinical outcome compared to the monotherapy group. These results, together with a review of the literature, lead us to the conclusion that there are no obvious advantages of carbamazepine co-medication in schizophrenia compared to an optimized neuroleptic monotherapy.

We report the case of a patient developing psychosis after the addition of mirtazapine, a novel antidepressant enhancing serotonergic neurotransmission, to a chronic levodopa regimen. There was complete and rapid recovery upon low-dose clozapine treatment. To our knowledge, this is the first published case of a mirtazapine-levodopa interaction and the second case report of a psychosis induced by a serotonergic antidepressant in a patient with Parkinson's disease (PD). This phenomenon might be due to a postsynaptic serotonin receptor supersensitization caused by low central serotonin levels in treated PD.

The new antiepileptic lamotrigine has been shown to be effective in the treatment of focal epilepsies with or without secondary generalization and has also been suggested to be efficacious in the treatment and prophylaxis of affective disorders. Therefore, we analyzed its possible benefit in a patient with refractory bipolar affective disorder. Lamotrigine (up to 150 mg/d) was added to valproate (2700 mg/d), substituting previously administered neuroleptics. A considerable improvement of the patient's condition was achieved several days after the beginning of lamotrigine co-administration, and lasted over the total follow-up period of more than one year. The plasma concentrations after total remission were in the range of 1.9 to 6.2 mg/l for lamotrigine and 57.1 to 95.2 mg/l for valproate. This positive action of lamotrigine is discussed in the context of the drug's elementary effects on sodium and calcium channels.

Catatonia is a rare but difficult-to-treat disorder. Here, we report on the case of a schizophrenic patient who developed several episodes of severe catatonia after suffering from adequately treated Lyme disease with encephalitis. The catatonic stupor was not responsive to typical neuroleptics and benzodiazepines. After the medication was changed to risperidone, there was a dramatic and persistent improvement of the patient's condition. Two relapses during the follow-up period over five years were caused by dose reductions. Risperidone might be a promising drug in the treatment of acute catatonia and in preventing further episodes.