Tiagabine appears not to be efficacious in the treatment of acute mania

Background: Because a GABAergic hypofunction has been implied in the pathop hysiology of mania, we have tested the antimanic properties of the GABA tra nsporter 1 inhibitor tiagabine. Method: An open trial was conducted in 8 acutely manic inpatients with DSM- IV bipolar I disorder, 2 of them with tiagabine monotherapy and 6 with tiag abine as an add-on to previously insufficient mood-stabilizing medication. The study duration was 14 days. Changes in psychopathology were assessed by the Bech-Rafaelsen Mania Rating Scale. Results: None of the patients showed clear-cut relief from manic symptoms d uring the 2-week observation period. In 2 patients, we saw pronounced side effects (nausea and vomiting in one and a generalized tonic-clonic seizure in the other). Conclusion: The results from this open trial suggest that tiagabine seems t o have no pronounced antimanic efficacy compared with standard treatments s uch as valproate, lithium, or neuroleptics. It also appears that rapid dosa ge increases for antimanic treatment can cause potentially severe side effe cts.