Use of lithium in the treatment of bipolar disorder in late-life.

Lithium is the oldest and still one of the most frequently prescribed mood stabilizers in the treatment of bipolar disorder. Nonetheless, the evidence for lithium efficacy in older patients with bipolar disorder is almost entirely extrapolated from younger adult patients. Here we review the literature on lithium in older patients with bipolar disorder, concentrating on the past 3 years. A definitive study demonstrating the efficacy and safety of lithium in older patients with bipolar disorder is still missing. However, several lines of indirect evidence suggest that it is beneficial and advantageous over other mood stabilizers in the acute and maintenance treatment of late-life bipolar disorder. In addition, lithium may have unique properties as a regenerative therapeutic with specific benefits in reducing the cognitive impairment and suicide rates associated with bipolar disorder across the adult lifespan. Aging-associated pharmacokinetic and pharmacodynamic changes as well as increased rates of medical comorbidities and polypharmacy predispose older patients to a higher risk of lithium toxicity. Careful monitoring and adjustment of lithium dosage is especially important in older adults to minimize the risk of toxicity.