Psychiatric reactions during tricyclic treatment of the elderly reconsidered

In a prospective study of all geriatric patients treated with tricyclic antidepressants over an 18-month period, a lower incidence of adverse psychiatric reactions than literature based on chart reviews has suggested was found. In only three of the 43 patients studied (7%) did a picture consistent with toxic delirium develop. None of the seven patients with senile dementia of the Alzheimer type suffered an adverse psychiatric reaction despite having achieved therapeutic blood levels of medication. Difficulties in determining the type and pathogenesis of untoward reactions that do occur as a source of error in establishing frequency are emphasized. The relationship of such reactions to the neurobiology of aging, the central anticholinergic syndrome, and the putative role of acetylcholine in contributing to the clinical picture of senile dementia of the Alzheimer type is discussed.