INTRODUCTION: Mental illness has a chronic course of illness with a number of clinical manifestations. Affected individuals experience significant functional, emotional, cognitive, and/or behavioral impairments. The growing prevalence of mental illness has been associated with significant social and economic costs. Indeed, the economic burden of mental illness is estimated to exceed $1.8 trillion USD over the next 30 years. A significant number of individuals affected by mental illness fail to respond to first-line treatment options. Therefore, there remains an unmet need for rapidly attenuating therapeutic options for mental health disorders with minimal social and economic burden. AREAS COVERED: The paucity of novel treatment options warrants a renewed investigation of psychedelic-based psychotherapy. Herein, the authors will evaluate the therapeutic potential of traditional psychedelics, psilocybin, and MDMA, in the treatment of mental illness with a narrative review of available literature. EXPERT OPINION: Psychedelics, such as psilocybin and MDMA, offer an alternative avenue of therapy for many mental health disorders. Available evidence indicates that psychedelics may offer a single-dose, rapid effect model that have robust effects with treatment-resistant mental disorders and a unique advantage as a possible monotherapy for mental illness. Novel clinical trials that evaluate the safety, tolerability, and efficacy in clinically representative populations are warranted.