Ayahuasca is a serotonergic-acting psychotropic brew of which one of the main uses in traditional cultures is as a medicine. This is the reason why in Western culture ayahuasca is popularly considered to have medicinal properties, even if it is used outside of its traditional context. But what are the evidences of efficacy as a therapeutic tool? Is ayahuasca safe? And what are its exact mechanisms of action?