A retrospective evaluation of plasma trazodone concentrations and clinical response in a primary care clinic

Trazodone has become a very popular second generation antidepressant. In our experience, trazodone levels are frequently obtained albeit interpretation/utility of these levels and purported normal ranges are in question. We analyzed 39 consecutive cases of major depressive disorder treated with trazodone in a primary care medical clinic. Thirty (79%) of subjects had a positive response. While a positive correlation existed between dosage and concentration of the parent drug, no dose-response correlation could be identified within this cohort. However, a minimum level of 250 ng/ml did appear necessary for a response. The overall utility/cost efficacy of second generation antidepressants, in the absence of well designed dose response studies, is questioned.