Medication options in the treatment of treatment-resistant depression

Aim: Less than half of those suffering major depressive episodes achieve remission with the first antidepressant provided and one-third of all patients suffering depression have a chronic condition. Clinical experience indicates that a substantial proportion of patients suffer treatment-resistant depression (TRD). Our aim is to explore the literature reporting the drug treatment of TRD, and to present such information as would be of interest to clinical psychiatrists. Method: Literature searches were conducted using PubMed and entering the words antidepressant, augmentation, combined antidepressants, treatment resistant depression and the names of individual antidepressant medications. Results: Most authors recommended that TRD should be first approached by reassessing the diagnosis, adding psychotherapy and attending to psychosocial factors. Details of the following pharmacological options were identified: (i) augmentation of the currently employed antidepressant with a medication which is not an antidepressant; (ii) change of anti-depressant; and (iii) addition of a second antidepressant to the current antidepressant, or commencement of a combination of two antidepressants. Conclusions: When monotherapy provided at the maximum manufacturer-recommended doses for 3-4 weeks has failed to provide remission in depression, the diagnosis should be confirmed, psychotherapy added and psychosocial factors should receive attention. In the sustained absence of remission, a better outcome may be obtained by augmenting the antidepressant, changing from a single-action to a double- or multiple-action drug, or by combining antidepressants.