Once-a-day dosage tricyclic antidepressant drug therapy: a survey

To assess current usage of once-a-day tricyclic antidepressant drug therapy for depression by private practicing and hospital psychiatrists in the United States, a questionnaire was mailed to 1,000 randomly selected individuals in each population. A telephone follow-up was made of 75 randomly chosen non-respondents in each group. The results disclosed a high percentage of prescribers of single daily dosages for a large patient population, many of whom have been treated for 3 months to 1 year or longer, often with dosages in excess of those in the package insert for each drug. There were no significant differences of opinion among respondents with respect to tolerance, safety, efficacy, advantages, disadvantages, and economy of this method of treatment. All respondents acknowledged that there is a minority of depressed patients for whom this therapy is unsuitable. For maintenance therapy, 81% consider single daily dosage treatment of depression efficacious; for initial therapy, 51%.