Hallucinogen Persisting Perception

Hallucinogen persisting perception disorder (HPPD) is a chronic disorder in which a person has non-psychotic flashbacks of visual hallucinations or distortions experienced during a previous hallucinogenic drug experience, usually lacking the same feelings of mental intoxication experienced before.


Cluster Number:
Wiki Number: W092
Diagnosis: Hallucinogen-Persisting Perception Disorder
US Patients:
World Patients:
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Symptoms: non-psychotic flashbacks of visual hallucinations from previous drug expereinces; often visual snow as distracting lights
Causes: prior use of hallucenogenic drugs, mescaline, MDMA (ecstasy)
Medications: cannabis worsens the effects; sedatives, sobriety from all psychoactive substances appears best
Therapies: talk therapy may help. 1 in 500,000 users may have chronic occurrences.

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The world-wide medical research
reports chosen for each diagnosis 

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PubMed article’s summary-abstract.

  • To treat or not to treat? High-potency benzodiazepine use in a case of comorbid hallucinogen persisting perception disorder and alcohol use disorder
    by Julie A Christensen on September 1, 2022

    Hallucinogen persisting perception disorder (HPPD) is characterized by visual disturbances that resemble psychedelic intoxication and linger after use has ceased. The most common substances precipitating HPPD, lysergic acid diethylamide (LSD) and psilocybin, are posited to do so via damage to serotonergic neurons involved in vision. Mr. N is a 37-year-old with a history of alcohol, cannabis, LSD, cocaine, and nicotine use disorders who described visual distortions that resolved when he drank...

  • Modalities of the psychedelic experience: Microclimates of set and setting in hallucinogen research and culture
    by Ido Hartogsohn on July 12, 2022

    Mid-20th-century American research on psychedelics evinced a stunning diversity of interpretations of hallucinogenic effects. While some researchers viewed psychedelics as invaluable tools for psychotherapy, others persisted in treating them as psychosis-inducing agents. As some groups considered psychedelics as catalysts for artistic creativity, others investigated their potential use as psychochemical weapons in the battlefield, or conversely as tools for spiritual ecstasy and revelation. This...

  • Hallucinogenic Persisting Perception Disorder: A Case Series and Review of the Literature
    by Hannah Ford on May 23, 2022

    CONCLUSIONS: HPPD presents with heterogeneous visual phenomena on a background of previous classic and non-classic hallucinogen use. Ophthalmic investigations are typically normal. The symptoms of HPPD in our case series overlap with the typical features of Visual Snow Syndrome (VSS). Patients presenting with VSS should be screened for past recreational drug use. The DSM-5 description of HPPD does not include visual snow, nyctalopia, photophobia or floaters. A revision of the diagnostic criteria...

  • Psychedelics: Alternative and Potential Therapeutic Options for Treating Mood and Anxiety Disorders
    by Henry Lowe on April 23, 2022

    The word "psychedelic" (psyche (i.e., the mind or soul) and delos (i.e., to show)) has Greek origin and was first coined by psychiatrist Humphry Osmond in 1956, who had been conducting research on lysergic acid diethylamide (LSD) at the time. Psychedelic drugs such as N,N-DMT/DMT (N,N-dimethyltryptamine), 5-MeO-DMT (5-methoxy-N,N-dimethyltryptamine), LSD (lysergic acid diethylamide), MDMA (3,4-methylenedioxymethamphetamine) and psilocybin have had significant value as an entheogen in spiritual,...