A number of medications are used to treat bipolar disorder.[49] The medication with the best evidence is lithium, which is effective in treating acute manic episodes and preventing relapses; lithium is also an effective treatment for bipolar depression.[84] Lithium reduces the risk of suicide, self-harm, and death in people with bipolar disorder.[85] It is unclear if ketamine is useful in bipolar as of 2015.[86]
Four anticonvulsants are used in the treatment of bipolar disorder. Carbamazepine effectively treats manic episodes, with some evidence it has greater benefit in rapid-cycling bipolar disorder, or those with more psychotic symptoms or a more schizoaffective clinical picture. It is less effective in preventing relapse than lithium or valproate.[87][88] Carbamazepine became a popular treatment option for bipolar in the late 1980s and early 1990s, but was displaced by sodium valproate in the 1990s.[citation needed] Since then, valproate has become a commonly prescribed treatment, and is effective in treating manic episodes.[89] Lamotrigine has some efficacy in treating bipolar depression, and this benefit is greatest in more severe depression.[90] It has also been shown to have some benefit in preventing further episodes, though there are concerns about the studies done, and is of no benefit in rapid cycling disorder.[91] The effectiveness of topiramate is unknown.[92] Depending on the severity of the case, anticonvulsants may be used in combination with lithium or on their own.[citation needed]
Antipsychotic medications are effective for short-term treatment of bipolar manic episodes and appear to be superior to lithium and anticonvulsants for this purpose.[49] However, other medications such as lithium are preferred for long-term use.[49] Olanzapine is effective in preventing relapses, although the evidence is not as solid as the evidence for lithium.[93] Antidepressants have not been found to be of any benefit over that found with mood stabilizers.[94]
Short courses of benzodiazepines may be used in addition to other medications until mood stabilizing become effective.[9