Acute response to methylphenidate as a predictor of outcome of treatment with TCAs in the elderly.

Acute response to a single-dose, nonblind administration of methylphenidate 20 mg predicted outcome of treatment with desipramine in 42 elderly depressed inpatients. Treatment outcome was not predicted by the methylphenidate challenge in 29 patients who received amitriptyline. These findings are consistent with Maas' biogenic amine hypothesis and are encouraging with respect to the clinical utility of the methylphenidate challenge in geriatric depression.