The
anticonvulsants valproate and
carbamazepine have efficacy in treating acute
mania, but their efficacy in treating acute
bipolar depression and preventing mood episodes remains uncertain. Despite this, and given their utility and widespread use, both are widely accepted as standard treatments for
bipolar disorder. All the newer
anticonvulsants that have become available during the last decade have been or are being assessed to determine their efficacy in the treatment of various phases of
bipolar disorder. Among the newer
anticonvulsants, some appear to have efficacy in treating core bipolar symptoms, while others have efficacy in treating psychiatric comorbidity such as
substance abuse or an
anxiety disorder.
Lamotrigine is the most widely studied and is effective in treating and preventing
bipolar depression, and it is the only
anticonvulsant approved by the U.S. Food and Drug Administration as a maintenance treatment for
bipolar disorder. Other newer
anticonvulsants,
levetiracetam,
oxcarbazepine,
phenytoin, and
zonisamide offer promise, but further studies are required before they can be recommended for routine use to treat
bipolar disorder.
Gabapentin and
topiramate do not appear to have efficacy in treating acute
mania, but their utility in
bipolar depression and prevention of mood episodes has not been studied in double-blind trials.
Pregabalin has utility in treating generalized
anxiety disorder, but it has not been studied in
bipolar disorder. Given the success of
lamotrigine in treating
bipolar disorder, further double-blind controlled trials of the newer
anticonvulsants in treating
bipolar disorder are warranted. This article summarizes current evidence from trials of
anticonvulsants in
bipolar disorder and makes recommendations for their clinical use.