Effect of Recommended Dosage Range on the Prescribing of Antidepressants

Abstract

The aim of the study was to explore the role that suggested dosage range may play in suboptimal prescribing practice of tricyclic antidepressants. Clinicians practising in adult psychiatry were shown a clinical vignette of melancholia (as per DSM-III-R). One of two questionnaires on treatment practices, specifying either 75-200 mg or 75-425 mg of an unnamed tricyclic antidepressant, were randomly distributed to subjects. A highly significant (p = 0.001) difference was found: those who were given a narrow dosage range prescribed an average of 82.5 mg/day less antidepressant than those for whom the dosage range had been widened, indicating that the range within which dosages are recommended affects prescribing practices. When erroneously constrained, the range may contribute toward sub-optimal prescribing practices and as a consequence toward treatment-resistant depression.

Evaluating the Impact of an Educational Program on Practice Patterns of Canadian Family Physicians Interested in Depression Treatment

“…A number of studies have reported significant deficiencies in the use of antidepressant medications by primary care physicians. 2,9,[68][69][70][71] Two recent randomized intervention trials found that more than 50% of patients in the "treatment-as-usual" group remained depressed 1 year later, in contrast to a 70% or greater recovery rate in the intervention group, 14,32 suggesting that inadequate medication dosing by primary care practitioners may be associated with suboptimal clinical outcome. It has been reported that inappropriate antidepressant use may contribute not only to poor treatment outcomes, but also to significant increases in health care costs.…”