Bidirectional interaction of valproate and lamotrigine in healthy subjects.

Objective: To evaluate the steady-state pharmacokinetics of lamotrigine and valproate at three dosing levels of lamotrigine in normal volunteers receiving steady-state therapeutic doses of valproate.

Methods: This was an open-label, randomized, three-way crossover study of 18 normal male volunteers. Subjects received oral valproate (500 mg Depakote twice a day) throughout the study.

Placebo-controlled study of the efficacy and safety of lamotrigine in patients with partial seizures. U.S. Lamotrigine Protocol 0.5 Clinical Trial Group.

We evaluated the efficacy and safety of lamotrigine (300 and 500 mg/day) as add-on therapy in a multicenter, randomized, double-blind, parallel-group, placebo-controlled study of 216 patients with refractory partial seizures. During 6 months of treatment, median seizure frequency decreased by 8% with placebo, 20% with 300 mg lamotrigine, and 36% with 500 mg lamotrigine. Seizure frequency decreased by > or = 50% in one-third of the 500-mg group and one-fifth of the 300-mg group.

Does sigma receptor antagonism predict clinical antipsychotic efficacy?

The psychotogenic actions of sigma receptor agonists, such as pentazocine, have led to the hypothesis that sigma receptor antagonists may be putative antipsychotic agents. In this study, BW234U, a selective but relatively weak sigma receptor antagonist was compared at two different dosage ranges with chlorpromazine and placebo in a double-blind randomized treatment trial in schizophrenic patients undergoing acute exacerbation. During the 4-week blinded treatment period, there was a modest drop in Brief Psychiatric Rating Scale (BPRS) score in the chlorpromazine group, however, neither dosage range of BW234U, nor placebo produced a significant drop in the BPRS.