Psychedelics are sometimes used in therapy because the use of certain plants and compounds can induce hallucinations to treat mental health disorders, like depression and post-traumatic stress disorder (PTSD). Compounds that doctors most frequently use in therapy include psilocybin mushrooms, LSD, and mescaline. Using psychedelics to treat mental health disorders is new, but research suggests that these psychedelics may help some people with symptoms, especially when other methods of treatment fail. Researchers do not know exactly how or why psychedelics work. They may “reset” the brain by altering neurotransmitter levels, induce a new perspective on life, or teach a person a new way of thinking. Other research also suggests these psychedelics increase suggestibility, making a person more open to ideas discussed in therapy.