Paroxetine, a selective serotonin reuptake inhibitor (SSRI) antidepressant, is considered to have fewer side-effects than a typical tricyclic antidepressant. As the elderly frequently suffer from adverse effects of psychotropic drugs, safeties and tolerance of paroxetine and their relationship with dose were studied in a double-blind study. Sixteen non-hospitalised depressed patients, aged 72-86 years, were recruited but 12 patients completed the study. Patients were randomly selected to receive either 15 mg or 30 mg paroxetine daily for 42 days in a double-blind study. A trained nurse made weekly home visits to monitor their medication and general conditions. Patients were assessed at the hospital on days 1, 7, 14, 28. and 42. There were four drop-outs during the first week of study due to lack of motivation, skin rash and upper gastrointestinal symptoms (n = 2). Plasma levels of paroxetine showed a dose-related increase in concentrations and indicated a good compliance. At the dosages used, no changes in blood pressure, heart rate, salivary volume, visual choice reaction time, critical flicker fusion threshold and short-term memory were observed in these patients. However, there was a significant improvement in their subjective symptoms (as assessed by a symptom check list and Hamilton Rating Scale) in the 30 mg group, indicating a feeling of well-being. Copyright (C) 1997 Elsevier Science Ireland Ltd.