An extended-release formulation of carbamazepine, available since 1997 for treatment of epilepsy, has now been approved under a new name, Equetro, for acute mania and mixed episodes of bipolar disorder. Although the drug was effective in some patients for up to 6 months, it has not been approved for maintenance treatment. Carbamazepine has not been shown to be more effective than lithium or valproate, and it can cause serious adverse effects.

Genetic Test for Carbamazepine-Induced Stevens-Johnson Syndrome Carbamazepine (Tegretol, Carbatrol, Equetro, and others), which is now used to treat not only epilepsy but also trigeminal neuralgia and manic episodes in patients with bipolar disorder,1 is a known cause of Stevens-Johnson syndrome (SJS). The incidence of carbamazepine-induced SJS in countries with mainly white populations is 1 to 6 per 10,000 new users of the drug, but Asian patients have a 10-fold higher incidence of this reaction. An association has been found between the human leukocyte antigen (HLA)-B*1502 allele and...

Oxcarbazepine, which is chemically similar to carbamazepine, and levetiracetam, a pyrrolidine acetamide chemically unrelated to other antiepileptic drugs, are the sixth and seventh drugs approved by the US Food and Drug Administration in the last five years for oral use in partial seizures.

Lamotrigine (la mo tri jeen; Lamictal - Burroughs Wellcome), a phenyltriazine derivative, has been approved by the US Food and Drug Administration for use in addition to other antiepileptic drugs in adults with partial seizures. Since this diagnostic category includes the largest number of patients with intractable epilepsy, new drugs with antiepileptic activity are usually tried first for this indication. Lamotrigine was first marketed abroad in 1990 and is now available in more than 50 other countries.

When used for the appropriate seizure type, antiseizure medications (ASMs) are roughly equivalent in efficacy. In addition to the seizure type, the choice of drug is usually based on factors such as ease of use, spectrum of activity, adverse effects, interactions with other drugs, presence of comorbid conditions, suitability for elderly persons and those with childbearing potential, and cost. Treatment should begin with a single drug, increasing the dosage gradually until seizures are controlled or adverse effects become unacceptable. If seizures persist, expert clinicians generally...

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Felbamate (Felbatol - Wallace Laboratories), a phenyl dicarbamate structurally similar to meprobamate (Equanil, and others), was recently approved by the US Food and Drug Administration for use alone or with other drugs in adults with partial seizures with or without secondary generalization. It was also approved for use in addition to other drugs in children with the multiple types of seizures associated with the Lennox-Gastaut syndrome, a severe epileptic encephalopathy.

Although lithium (Eskalith, and others) is the standard treatment for bipolar (manic-depressive) disorder, 20% to 40% of patients do not respond adequately or cannot tolerate its adverse effects (Medical Letter, 33:43, 1991). Results of recent studies suggest that valproate (Depakene - valproic acid; Depakote - divalproex sodium), a widely used anticonvulsant (Medical Letter, 31:1, 1989), might be an effective alternative. Other anticonvulsants, particularly carbamazepine (Tegretol, and others), have also been used as second-line drugs for treatment of mania and other psychiatric ...

Tiagaine (Gabitril - Abbot), a gamma-aminobutyric acid (GABA) uptake inhibitor, has been approved by the FDA for oral use as an adjunct to other drugs for treatment of partial seizures in patients more than 12 years old. Since most adult patients with resistant epilepsy have partial seizures, new antiepileptic drugs are usually tried first for this indictation.

Bipolar disorder is characterized by episodes of mania, hypomania, and depression. Recurrences of manic or (more frequently) depressive symptoms are common. About 15-20% of patients with bipolar disorder die by suicide.