Bipolar Disorder

Anticonvulsant medications, particularly valproate and carbamazepine, have been used as alternatives or adjuncts to lithium in many cases. Valproate (Depakote and Depakene, Epival) was FDA approved for the treatment of acute mania in 1995, and is now considered by some doctors to be the first line of therapy for bipolar disorder. For some, it is preferable to lithium because its side effect profile seems to be less severe, compliance with the medication is better, and fewer breakthrough manic episodes occur. However, valproate is not as effective as lithium in preventing or managing depressive episodes, so patients taking valproate may also need an antidepressant as an adjunct medicinal therapy.

New research suggests that different combinations of lithium and anticonvulsants may be helpful. Anticonvulsants are also used in combination with antipsychotics. Newer anticonvulsant medications, including lamotrigine and oxcarbazepine, are also effective as mood stabilizers in bipolar disorder. Lamotrigine is particularly promising, as it alleviates bipolar depression and prevents recurrence at higher rates.

Zonisamide (trade name Zonegran), another anticonvulsant, also may show promise in treating bipolar depression according to Frederick K. Goodwin M.D. on a recent Medscape webcast titled “The Accurate Diagnosis and Long-Term Treatment of Bipolar Depression”.
Topiramate has not done well in clinical trials, it seems to help a few patients very much but most not at all. It appears to be useful in some treatment resistant cases and for anxiety issues when clonazepam cannot be prescribed. Gabapentin has failed to distinguish itself from placebo as a mood stabilizer.

According to studies conducted in Finland in patients with epilepsy, valproate may increase testosterone levels in teenage girls and produce polycystic ovary syndrome in women who began taking the medication before age 20. Increased testosterone can lead to polycystic ovary syndrome with irregular or absent menses, obesity, and abnormal growth of hair. Therefore, young female patients taking valproate should be monitored carefully by a physician. However, the therapeutic dose for a patient taking valproate for epilepsy is much higher than the therapeutic dose of valproate for an individual with bipolar disorder.

Other anticonvulsants effective in some cases and being studied closer include phenytoin, levetiracetam, pregabalin and valnoctamide.