Medical & Clinical Reviews

Hallucinogen-Induced Persisting Perception Disorder

Hallucinogenpersisting perception disorder (HPPD) is a drug-induced condition associated with inaccurate visual representations. Since the underlying mechanism(s) are largely unknown, this review aims to uncover aspects underlying its etiology. Available evidence on HPPD and drug-related altered visual processing was reviewed and the majority of HPPD cases were attributed to drugs with agonistic effects on serotonergic 5-HT2Areceptors.

Hallucinogen persisting perception disorder(HPPD) is a chronic and non-psychotic disorder in nwhich a person experiences apparent lasting or persistent visual hallucinations or perceptual distortions after a previoushallucinogenicdrug experience, usually lacking the same feelings of intoxication ormental alterationexperienced while on the drug. The hallucinations and perceptual changes consist ofvisual snow, trails and after images (palinopsia), light fractals on flat surfaces, intensified colors or other psychedelic visuals.

Hallucinogen use is widespread. In the United States, 16.9% of young adults report having used hallucinogens (Johnston et al., 2008). Although most hallucinogen use apparently occurs without adverse events, there have long been reports of prolonged or reoccurring perceptual changes in a subset of hallucinogen users (Asher, 1971; Rosenthal, 1964; Smart and Bateman, 1967).

Author(s):

Alan Dubro*

Abstract | Full-Text | PDF

Share this