Treatment-resistant depression: Established and emerging therapies.

In 2023, the percentage of people in the US who experienced depression in their lifetime was at an all-time high of 29%. Depression causes considerable distress and functional impairment affecting quality of life, employment, and interpersonal relationships. Many patients fail to respond to treatment with antidepressants and psychological-behavioral therapy, resulting in a condition known as treatment-resistant depression (TRD). TRD contributes to negative outcomes for patients and increased costs to the healthcare system. Recognizing TRD and understanding TRD interventions are important aspects of practice for clinicians in treating this patient population. This article reviews current and emerging TRD treatments, including electroconvulsive therapy, ketamine, esketamine, and transcranial magnetic stimulation, to inform NP practice.