Lamotrigine use in geriatric patients with bipolar depression.

OBJECTIVE To study the effectiveness of adding lamotrigine to the treatment of inpatient geriatric patients with bipolar disorder (BD) who were in the depressed phase and had been on lithium and valproate for at least 3 months. METHOD Lamotrigine was started at 25 mg given at bedtime, with weekly incremental increases of 12.5 mg daily until a total dosage of either 75 mg or 100 mg was obtained. Improvement was measured by clinical interview and Hamilton Depression Rating Scale (HDRS) scores. Patients were reassessed at 6 weeks, and if their HDRS score had decreased by at least 50%, they were considered to have improved. RESULTS The study group comprised 5 women with an average age of 71.5 years (range 65 to 85). Four had rapid-cycling BD, and 1 had mixed BD. All patients had early age of onset, as judged by their first contact with a psychiatrist or their first hospitalization. The average initial HDRS score was 27 (range 20 to 35). Of the patients, 3 out of the 5 had remission of symptoms, as judged by clinical interview and reduction of their HDRS score by 50%. At 3 months follow-up, these 3 patients had not required rehospitalization and were doing well. Lamotrigine was well tolerated, and none of the patients developed a rash. One patient did develop coarse hand tremor that improved when the lamotrigine dosage was decreased. CONCLUSIONS Lamotrigine in conjunction with lithium and valproate may be effective in treating geriatric patients with BD and depression.