Tricyclic antidepressants have proven effective in treating depressed HIVpositive patients in both controlled (Manning et al., 1990; Rabkin et al., 1994) and open clinical studies (Rabkin and Harrison, 1990; Fernandez and Levy, 1991). HIVinfected patients are similar to geriatric patients in their response to the administration of antidepressants. They can respond to lower dosages of tricyclics (25-100 mg), but they may also suffer severe anticholinergic effects at reduced dosages. Therefore, the choice of an antidepressant for these patients should be guided, by its side effects profile. The administration of agents with a high affinity for central muscarine receptors should be avoided, since their anticholinergic effects could aggravate cognitive difficulties to the point of triggering delirium episodes. In addition, they produce dryness in the mucous membranes, which could favour the development of candidiasis. Due to its milder side effects on the autonomic nervous system, nortriptyline is a useful drug here.