To the Editor: Although the safety of lamotrigine for the epileptic population is known (1), clinical experience in elderly patients with bipolar disorder is limited.
Ms. A was a 76-year-old woman with a 50-year history of bipolar disorder. She had been successfully treated with lamotrigine, 75 mg/day, for 34 months without a recurrence of mood episodes. Before treatment with lamotrigine, while receiving ECT, she experienced major depressive symptoms of sadness, worthlessness, diminished interest, poor concentration and energy, and sleep disturbance. Her functioning while taking lamotrigine was superior to that experienced while she was receiving ECT. Minor adverse effects, some agitation and sleep disturbance, were treated with a dose reduction, from 100 mg/day to 75 mg/day.
Ms. A had taken lithium for 21 years for bipolar disorder. She functioned well, with no manic or major depressive episodes. She developed renal insufficiency, and her lithium therapy was discontinued. Her creatinine level had remained stable, in the 2.0–2.4 mg/dl range. When lithium therapy was discontinued in 1989, she began to cycle. Her recurrent major depressive episodes became quite severe. Over the next 6 years, she maintained a carbamazepine level of 8.6 μg/ml, with the addition of bupropion, nortriptyline, sertraline, and fluoxetine, but she experienced no improvement in her depressive symptoms. She continued to have mild depression and agoraphobia-like anxiety. She had routine CBC counts and thyroid and renal function laboratory monitoring. Because of her increasing problems with depression, ECT was considered. Ms. A had two brief courses of ECT in the 1950s with excellent results, but she has negative memories of those treatments.
Ms. A received a course of 12 ECT treatments in 1996, followed by maintenance treatments every 4–6 weeks, which she dreaded. She tolerated the treatments well and had no mania, but she never returned to the mood state she had achieved with lithium therapy. Ms. A and her husband sought alternative therapies; lamotrigine was discussed as a possible alternative therapy (2, 3).
Ms. A’s local psychiatrist initiated treatment with lamotrigine, 12.5 mg every other day for 1 week, followed by 12.5 mg/day for 1 week, 25 mg/day for 1 week, then up to 50 mg/day, and ultimately to 100 mg/day. Ms. A returned to a euthymic state, with functioning superior to that experienced while she was receiving ECT and rivaling that experienced while she was taking lithium. Ms. A has maintained a high level of functioning and has actively participated in her community for 34 months.
This case report suggests that lamotrigine may be well tolerated and effective in the treatment of bipolar disorder in the geriatric population.