Increasing evidence indicates that subtypes of bipolar disorder differ not only in symptomatology and associated clinical features, but by differences in age at onset, illness course, and response to treatment. Secondary manic states differ from typical bipolar states and are often especially difficult to treat. Although the correction of the underlying organic factors (toxic, metabolic, or infectious) may effectively reverse the manic presentation, many organic factors are not reversible (trauma, stroke, and aging), and the presence of these etiologic factors can complicate traditional antimanic treatments. Lithium may be effective for treating patients with secondary mania, but data from published studies show that in this population the associated adverse effects often limit its usefulness. Anticonvulsants appear to offer an effective alternative. Divalproex sodium, in particular, has been shown to be an effective and well-tolerated treatment in open trials in the elderly and other patient groups with secondary mania. Controlled clinical trials are necessary to confirm the efficacy and tolerability of mood-stabilizing anticonvulsants in the treatment of secondary mania.