Editing LSD (section)

====Flashbacks====
{{See also|Urban legends about drugs#"Permatripping" and retention of LSD in spinal fluid}}

[[Flashback (psychology)|Flashbacks]] are psychological episodes where individuals re-experience some of LSD's subjective effects after the drug has worn off, persisting for days or months post-[[hallucinogen]] use.<ref name="Halpern2003">{{cite journal |vauthors=Halpern JH, Pope HG |title=Hallucinogen persisting perception disorder: what do we know after 50 years? |journal=Drug and Alcohol Dependence |volume=69 |issue=2 |pages=109–19 |date=March 2003 |pmid=12609692 |doi=10.1016/S0376-8716(02)00306-X}}</ref><ref>{{cite journal |vauthors=Müller F, Kraus E, Holze F, Becker A, Ley L, Schmid Y, Vizeli P, Liechti ME, Borgwardt S |title=Flashback phenomena after administration of LSD and psilocybin in controlled studies with healthy participants |journal=Psychopharmacology |date=January 2022 |volume=239 |issue=6 |pages=1933–1943 |pmid=35076721 |doi=10.1007/s00213-022-06066-z |pmc=9166883 |s2cid=246276633}}</ref> These experiences are associated with [[hallucinogen persisting perception disorder]] (HPPD), where flashbacks occur intermittently or chronically, causing distress or functional impairment.<ref name="Halpern2018">{{cite book |title=A Review of Hallucinogen Persisting Perception Disorder (HPPD) and an Exploratory Study of Subjects Claiming Symptoms of HPPD. |vauthors=Halpern JH, Lerner AG, Passie T |date=2018 |isbn=978-3-662-55878-2 |series=Current Topics in Behavioral Neurosciences |volume=36 |pages=333–360 |doi=10.1007/7854_2016_457 |pmid=27822679}}</ref>

The etiology of flashbacks is varied. Some cases are attributed to [[somatic symptom disorder]], where individuals fixate on normal [[Somatic nervous system|somatic]] experiences previously unnoticed prior to drug consumption.<ref>{{cite journal |vauthors=Johansen PØ, Krebs TS |title=Psychedelics not linked to mental health problems or suicidal behavior: a population study |journal=Journal of Psychopharmacology |volume=29 |issue=3 |pages=270–279 |date=March 2015 |doi=10.1177/0269881114568039 |pmid=25744618 |s2cid=2025731}}</ref> Other instances are linked to associative reactions to contextual cues, similar to responses observed in individuals with past trauma or emotional experiences.<ref>{{cite book |vauthors=Holland D, Passie T |isbn=978-3-86135-207-5 |language=de |year=2011 |title=Flashback-Phänomene als Nachwirkung von Halluzinogeneinnahme |volume=2 |series=Bewusstsein – Kognition – Erleben |publisher=VWB Report |url=http://www.vwb-verlag.com/Katalog/m207.html |access-date=June 9, 2023 |archive-date=June 9, 2023 |archive-url=https://web.archive.org/web/20230609015208/http://www.vwb-verlag.com/Katalog/m207.html |url-status=live }}</ref> The risk factors for flashbacks remain unclear, but pre-existing psychopathologies may be significant contributors.<ref>{{cite journal |vauthors=Abraham HD, Duffy FH |date=October 1996 |title=Stable quantitative EEG difference in post-LSD visual disorder by split-half analysis: evidence for disinhibition |journal=Psychiatry Research |volume=67 |issue=3 |pages=173–87 |pmid=8912957 |doi=10.1016/0925-4927(96)02833-8 |s2cid=7587687}}</ref>

Estimating the prevalence of HPPD is challenging. It is considered rare, with occurrences ranging from 1 in 20 users experiencing the transient and less severe type 1 HPPD, to 1 in 50,000 for the more concerning type 2 HPPD.<ref name="Halpern2018"/> Contrary to [[Urban legends about drugs#"Permatripping" and retention of LSD in spinal fluid|internet rumors]], LSD is not stored long-term in the [[spinal cord]] or other parts of the body. Pharmacological evidence indicates LSD has a half-life of 175 minutes and is metabolized into water-soluble compounds like 2-oxo-3-hydroxy-LSD, eliminated through urine without evidence of long-term storage.<ref name="PassieHalpernStrichtenoth2008" /> Clinical evidence also suggests that chronic use of [[SSRI]]s can potentiate LSD-induced flashbacks, even months after stopping LSD use.<ref name="drug-interaction">{{cite book |title=Psychedelics as Psychiatric Medications |publisher=[[Oxford University Press]] |isbn=9780192678522 |url=https://books.google.com/books?id=7lazEAAAQBAJ |date=7 March 2023 |vauthors=Nutt DJ, Castle D |chapter=Drug-interaction with psychotropic drugs |access-date=May 21, 2023 |archive-date=May 21, 2023 |archive-url=https://web.archive.org/web/20230521000115/https://books.google.com/books?id=7lazEAAAQBAJ |url-status=live }}</ref>{{rp|145}}