Anecdotal evidence indicates that the symptoms of OCD are mitigated by hallucinogens, and the newly recognized 5-HT2A receptor promoter polymorphism provides the likely mechanism for this effect. Three reports have surfaced in the literature of individuals with long-standing OCD who experienced significant alleviation of their disorder after what was initially a "recreational" use of LSD, peyote, or Psilocybe mushrooms. The most recent of these (5) relates that a 34-year-old man who had suffered from OCD since the age of 6 found that both peyote and Psilocybe mushrooms moderated his symptoms (which included incapacitating and compulsive counting, showering, and ritualistic washing of his clothes, hands, and body). He began a 4-year course of daily Psilocybe mushroom ingestion, which resulted in improvement of his OCD symptoms, unaccompanied by any hallucinogenic effects because of his acquired tolerance. During a subsequent 2-year period, his OCD remained in control without the need for him to ingest Psilocybe, but then the symptoms gradually returned to their initial levels.