This monograph summarizes the proceedings of a roundtable meeting convened to discuss the role of carbamazepine in the treatment of bipolar disorder, in light of new data and the recent indication of carbamazepine extended-release capsules (CBZ ERC) for use in the treatment of acute manic and mixed episodes. Two lectures were presented, followed by a panel discussion among all 6 participants. A summary of the two pivotal trials of CBZ ERC and their pooled data along with other relevant data is presented first. Next, historical trends of carbamazepine and the agent's use in acute mania, bipolar depression, and maintenance are reviewed, emphasizing clinical implications of efficacy, safety, tolerability, and drug interactions. Finally, the panel discussion provides recommendations for the use of carbamazepine in different phases of the illness, taking into account adverse effects and drug-drug interactions.

Panel discussants agree that current data confirm the utility of CBZ ERC as an effective treatment for acute manic and mixed episodes in bipolar disorder. Carbamazepine may also prove to be an option for maintenance treatment. Tolerability of the drug is related to dose and titration, and overall safety limitations regarding carbamazepine usage are comparable to other medications. For some patients, the main challenges to use of carbamazepine may be common drug-drug interactions and increased side effects related to aggressive introduction during treatment of acute manic and mixed episodes. Thus, carbamazepine may be a lower priority option for patients who are taking multiple medications, such as elderly individuals with medical comorbidity, due to the potential for drug interactions. Important benefits of carbamazepine include the low propensity toward weight gain and evidence of good tolerability with long-term treatment. (At present there are no available data from long-term, placebo-controlled studies evaluating the effects of carbamazepine or CBZ ERC on weight. *) Thus, carbamazepine may be a good option for patients who are concerned about weight gain or who are intolerant of or respond poorly to other medications. Further efforts are needed to update physicians on the use of carbamazepine relative to other medications in the treatment of bipolar disorder.

This discussion reviews data from two 3-week, double-blind, placebo-controlled pivotal trials of carbamazepine extended release capsules (CBZ ERC; SPD417.301 and SPD417.304); pooled results from these trials; data from a 3-week, double-blind, placebo-controlled trial in lithium non-responders or non-tolerators (SPD417.302); and additional supportive data from a 6-month, open-label, extension trial (SPD417.303). In addition, information on a retrospective chart review of 600 adolescent and adult bipolar patients on CBZ ERC is presented.

In the first large double-blind, placebo-controlled study assessing CBZ ERC in acute mania, manic and mixed bipolar patients from multiple centers were hospitalized and all medications were discontinued. After reaching a stable baseline 2–5 days later, the patients were randomized to CBZ ERC (n=101; 59% with mixed states) or placebo (n=103; 47% with mixed states) for 3 weeks. An aggressive initial titration schedule was implemented, beginning with 200 mg BID and increased by 200 mg/day until good clinical response was achieved or the patient could not tolerate the dosage. Many patients were taking 1,200–1,600 mg/day by the end of week 1. Efficacy was assessed using the Young Mania Rating Scale (YMRS). The Clinical Global Impressions (CGI) scale and the Hamilton Rating Scale for Depression (HAM-D) were also followed.

This discussion focuses on the historical trends of carbamazepine in the treatment of acute mania, acute bipolar depression, and as maintenance treatment for bipolar disorder. Clinical implications of efficacy, safety, tolerability, and drug interactions associated with carbamazepine are discussed as well.

Important progress in bipolar disorders therapeutics began in the 1970s with lithium and the conventional antipsychotics, and continued in the 1980s with carbamazepine, in the 1990s with divalproex, and in the 2000s with lamotrigine and the introduction of the atypical antipsychotics. Electroconvulsive therapy (ECT) has been used throughout these periods and still has a place in bipolar disorder, especially for severe, treatment-resistant, and very acute cases.