All of the following drugs are indicated in the treatment of bipolar disorder except?

BIPOLAR DISORDER Drug of choice for bipolar disorder is lithium. Alternatives to lithium are some antiepileptics (carbamazepine, valproate, lamotrigine, topiramate), antipsychotics (olanzapine, aripiprazole, haloperidol) and benzodiazepines. Carbamazepine and valproate are useful in manic depressive psychosis (bipolar disorder). These can also be used for acute mania. Valproic acid is the drug of choice for treatment of rapid cyclers (> 4 cycles/year). Lamotrigine is specifically useful for depressive phase of bipolar disorder. It is the first agent to be approved by FDA for bipolar disorder without an indication for acute mania. Benzodiazepines like lorazepam are the drugs of choice for acute mania when combined with lithium. Olanzapine and other atypical antipsychotics show efficacy in bipolar disorder as well as acute mania.