Comparing triggers to visual disturbances among individuals with positive vs negative experiences of hallucinogen-persisting perception disorder (HPPD) following LSD use

Am J Addict. 2017 Sep;26(6):568-571. doi: 10.1111/ajad.12577. Epub 2017 Jun 27.


Background and ojective: Exploring differences in visual disturbances and triggers between Hallucinogen-Persisting-Perceptual-Disorder (HPPD) Type I ("positive/benign") and II ("negative/distressing").

Methods: Forty individuals with HPPD and prior LSD use completed clinical questionnaires.

Results: The most common type of visual disturbances among individuals with HPPD I and II was slow movement of still objects and trailing phenomena, respectively. Those with HPPD I were more likely to report experiencing disturbances in dark environment, while looking at a still or moving object and during sexual intercourse.

Discussion and conclusions: HPPD I and II differ in terms of visual disturbances and triggers, possibly representing different phenomena existing on the same spectrum.

Scientific significance: Our study indicating differences in triggers to HPPD I and II adds to existing literature on differences in visual disturbances between the two subtypes. Further research elucidating additional differences between the subtypes of HPPD is needed. (Am J Addict 2017;26:568-571).

MeSH terms

  • Adult
  • Agnosia / psychology
  • Female
  • Hallucinations / psychology*
  • Hallucinogens / pharmacology
  • Humans
  • Lysergic Acid Diethylamide / pharmacology*
  • Male
  • Perceptual Disorders / psychology*
  • Surveys and Questionnaires
  • Visual Perception / drug effects*


  • Hallucinogens
  • Lysergic Acid Diethylamide