Augmentation strategies for treatment-resistant depression

Purpose of review The majority of patients with depression fail to remit on one or more antidepressant trials. These patients have treatment-resistant depression (TRD) with high relapsing rates. Augmentation pharmacotherapy refers to the addition of drugs that are not standard antidepressants in order to enhance the effect of a classical antidepressant drug. This review highlights the current status and future research directions of augmentation treatments for TRD with a special focus on research data published within the past year. Recent findings Atypical antipsychotics, stimulants, pindolol, lithium, lamotrigine and mecamylamine were tested for efficacy in clinical trials. Most of the trials were not controlled or had limited sample size. Recent data now support the use of some atypical antipsychotics to augment depression resistant to the newer, more selective, antidepressants. Summary Lithium and triiodothyronin (T3) augmentation of tricyclic agents remains the best studied strategy. Data converge to demonstrate the efficacy of some atypical antipsychotics as augmenting agents to selective serotonin reuptake inhibitors. Further adequately powered controlled trials on augmentation pharmacotherapy of TRD are necessary.