Frontiers in Neurology

Hallucinogenic Persisting Perception Disorder: A Case Series and Review of the Literature

This retrospective series of 13 patients and review of 24 case reports found that HPPD commonly causes visual snow, floaters, palinopsia, photophobia and nyctalopia despite normal ophthalmic and neurological investigations, producing a phenotype that overlaps substantially with Visual Snow Syndrome. The authors argue DSM‑5 diagnostic criteria should be expanded to include these symptoms, that VSS patients be screened for prior hallucinogen use, and that controlled studies compare primary and secondary VSS to clarify pathophysiology and treatment.

Published

May 6, 2022

Journal

Frontiers in Neurology

Authors

Van Der Walt, A., Ford, H., Fraser, C. L., Solly, E., Clough, M., Fielding, J., White, O.