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Intoxication from LSD and other common hallucinogens

João Delgado, MD
Section Editor
Stephen J Traub, MD
Deputy Editor
Jonathan Grayzel, MD, FAAEM


"Hallucinogen" describes substances whose primary effects include the alteration of sensory perception, mood, and thought patterns. Naturally occurring hallucinogens have been used for millennia as part of ritual and religious activities. The first synthetic hallucinogen, lysergic acid diethylamide (LSD), was synthesized in 1938 by the chemist Albert Hofmann. Its hallucinogenic properties were recognized by accident in 1943 when Dr. Hofmann was inadvertently exposed to LSD while working in his laboratory [1]. LSD was initially marketed as an anesthetic agent and touted as an adjunct for psychoanalysis. In the 1960s, LSD emerged as a recreational drug. Its popularity peaked in the late 1960s and early 1970s and has been declining since. The drug was banned under United States federal law in 1966.

Hallucinogens are used for their so-called psychedelic effects. These desired effects involve heightening or distortion of sensory stimuli and enhancement of feelings and introspection. Most hallucinogens produce sympathomimetic effects, including tachycardia, hypertension, mydriasis, hyperthermia, and diaphoresis, but these are generally mild [2]. Nausea and vomiting are common and often precede the onset of hallucinogenic effects.

The clinical features, diagnosis, and management of intoxication from LSD and other prototypical hallucinogens (including dextromethorphan, some phenylethylamines (mescaline, 2CB, 2CT-7), psilocybin and other tryptamines, and Salvia divinorum) are reviewed here (table 1). Amphetamines, methamphetamines, MDMA, ketamine, and phencyclidine (PCP) are discussed separately. (See "Methamphetamine intoxication" and "MDMA (ecstasy) intoxication" and "Ketamine poisoning" and "Phencyclidine (PCP) intoxication in adults".)


Lysergic acid diethylamide (LSD) remains the prototypical hallucinogen and the most extensively studied of such drugs. It is estimated that approximately 4.2 million persons in the United States used hallucinogens in 2014, mostly adolescents and young adults [3]. Hallucinogens account for approximately 7 percent of United States emergency department (ED) visits involving illicit drugs [4]. Hallucinogen use occurs worldwide, although the prevalence is generally considered to be low relative to other drugs of abuse [5]. LSD has been supplanted as the most common hallucinogen by "club drugs", synthetic cannabinoids (eg, K2, spice) and naturally occurring hallucinogens, such as psilocybin and Salvia divinorum [5,6]. This is thought to be related to a number of factors, including the decreased supply of LSD, the emergence of "club drugs", such as ecstasy, and the ready availability of other hallucinogens via the internet [7,8].


A hallucination occurs when a person experiences sensory perceptions in the absence of external stimuli. True hallucinations can occur with recreational hallucinogen use. However, the alterations in perception commonly caused by these drugs are more accurately termed illusions because there is often a basis in reality for the sensory perception.


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Literature review current through: Sep 2016. | This topic last updated: Apr 13, 2016.
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  1. Hoffman A. LSD: my problem child. Ott, J (Trans), McNaughton & Gunn; Saline, MI 2005.
  2. Blaho K, Merigian K, Winbery S, et al. Clinical pharmacology of lysergic acid diethylamide: case reports and review of the treatment of intoxication. Am J Ther 1997; 4:211.
  3. Substance Abuse and Mental Health Services Administration, Center for Behavioral Health Statistics and Quality, National Survey on Drug Use and Health, 2013 and 2014.
  4. Substance Abuse and Mental Health Services Administration, Drug Abuse Warning Network, 2011: National Estimates of Drug-Related Emergency Department Visits. HHS Publication No. (SMA) 13-4760, DAWN Series D-39. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2013.
  5. United Nations Office on Drugs and Crime (UNODC). World Drug Report 2012. https://www.unodc.org/documents/data-and-analysis/WDR2012/WDR_2012_web_small.pdf (Accessed on May 27, 2014).
  6. Johnston LD, O'Malley PM, Bachman JG, Schulenberg JE. Monitoring the Future. National results on adolescent drug use: Overview of key findings, 2007. Publication no. 08-6418., National Institute on Drug Abuse, Bethesda, MD 2008.
  7. Hoover V, Marlowe DB, Patapis NS, et al. Internet access to Salvia divinorum: implications for policy, prevention, and treatment. J Subst Abuse Treat 2008; 35:22.
  8. Lange JE, Reed MB, Croff JM, Clapp JD. College student use of Salvia divinorum. Drug Alcohol Depend 2008; 94:263.
  9. Lerner AG, Gelkopf M, Skladman I, et al. Clonazepam treatment of lysergic acid diethylamide-induced hallucinogen persisting perception disorder with anxiety features. Int Clin Psychopharmacol 2003; 18:101.
  10. Nichols DE. Hallucinogens. Pharmacol Ther 2004; 101:131.
  11. Fantegrossi WE, Murnane KS, Reissig CJ. The behavioral pharmacology of hallucinogens. Biochem Pharmacol 2008; 75:17.
  12. Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med 2005; 352:1112.
  13. Roth BL, Baner K, Westkaemper R, et al. Salvinorin A: a potent naturally occurring nonnitrogenous kappa opioid selective agonist. Proc Natl Acad Sci U S A 2002; 99:11934.
  14. Halpern JH, Pope HG Jr. Do hallucinogens cause residual neuropsychological toxicity? Drug Alcohol Depend 1999; 53:247.
  15. Callaway CW, Clark RF. Hyperthermia in psychostimulant overdose. Ann Emerg Med 1994; 24:68.
  16. Drug Enforcement Administration, US Department of Justice. Drugs and Chemicals of Concern. http://www.deadiversion.usdoj.gov/drugs_concern (Accessed on July 24, 2012).
  17. Richardson WH 3rd, Slone CM, Michels JE. Herbal drugs of abuse: an emerging problem. Emerg Med Clin North Am 2007; 25:435.
  18. Al-Assmar SE. The seeds of the Hawaiian baby woodrose are a powerful hallucinogen. Arch Intern Med 1999; 159:2090.
  19. Klock JC, Boerner U, Becker CE. Coma, hyperthermia and bleeding associated with massive LSD overdose. A report of eight cases. West J Med 1974; 120:183.
  20. Lieberman AN, Bloom W, Kishore PS, Lin JP. Carotid artery occlusion following ingestion of LSD. Stroke 1974; 5:213.
  21. Raval MV, Gaba RC, Brown K, et al. Percutaneous transluminal angioplasty in the treatment of extensive LSD-induced lower extremity vasospasm refractory to pharmacologic therapy. J Vasc Interv Radiol 2008; 19:1227.
  22. Bullis RK. Swallowing the scroll: legal implications of the recent Supreme Court peyote cases. J Psychoactive Drugs 1990; 22:325.
  23. Kyriakou C, Marinelli E, Frati P, et al. NBOMe: new potent hallucinogens--pharmacology, analytical methods, toxicities, fatalities: a review. Eur Rev Med Pharmacol Sci 2015; 19:3270.
  24. Lawn W, Barratt M, Williams M, et al. The NBOMe hallucinogenic drug series: Patterns of use, characteristics of users and self-reported effects in a large international sample. J Psychopharmacol 2014; 28:780.
  25. Gee P, Schep LJ, Jensen BP, et al. Case series: toxicity from 25B-NBOMe--a cluster of N-bomb cases. Clin Toxicol (Phila) 2016; 54:141.
  26. Miyajima M, Matsumoto T, Ito S. 2C-T-4 intoxication: acute psychosis caused by a designer drug. Psychiatry Clin Neurosci 2008; 62:243.
  27. D'Onofrio G, McCausland JB, Tarabar AF, Degutis LC. Illy: clinical and public health implications of a street drug. Subst Abus 2006; 27:45.
  28. McCarron MM, Schulze BW, Thompson GA, et al. Acute phencyclidine intoxication: incidence of clinical findings in 1,000 cases. Ann Emerg Med 1981; 10:237.
  29. McCarron MM, Schulze BW, Thompson GA, et al. Acute phencyclidine intoxication: clinical patterns, complications, and treatment. Ann Emerg Med 1981; 10:290.
  30. Halpern JH. Hallucinogens and dissociative agents naturally growing in the United States. Pharmacol Ther 2004; 102:131.
  31. Grob CS, Danforth AL, Chopra GS, et al. Pilot study of psilocybin treatment for anxiety in patients with advanced-stage cancer. Arch Gen Psychiatry 2011; 68:71.
  32. Boyer EW, Shannon M, Hibberd PL. The Internet and psychoactive substance use among innovative drug users. Pediatrics 2005; 115:302.
  33. Johnson MW, MacLean KA, Reissig CJ, et al. Human psychopharmacology and dose-effects of salvinorin A, a kappa opioid agonist hallucinogen present in the plant Salvia divinorum. Drug Alcohol Depend 2011; 115:150.
  34. Taylor RL, Maurer JI, Tinklenberg JR. Management of "bad trips" in an evolving drug scene. JAMA 1970; 213:422.
  35. Solursh LP, Clement WR. Use of diazepam in hallucinogenic drug crises. JAMA 1968; 205:644.
  36. Nobay F, Simon BC, Levitt MA, Dresden GM. A prospective, double-blind, randomized trial of midazolam versus haloperidol versus lorazepam in the chemical restraint of violent and severely agitated patients. Acad Emerg Med 2004; 11:744.
  37. Knott JC, Taylor DM, Castle DJ. Randomized clinical trial comparing intravenous midazolam and droperidol for sedation of the acutely agitated patient in the emergency department. Ann Emerg Med 2006; 47:61.
  38. Spain D, Crilly J, Whyte I, et al. Safety and effectiveness of high-dose midazolam for severe behavioural disturbance in an emergency department with suspected psychostimulant-affected patients. Emerg Med Australas 2008; 20:112.
  39. Maslanka AM, Scott SK. LSD overdose in an eight-month-old boy. J Emerg Med 1992; 10:481.
  40. Ianzito BM, Liskow B, Stewart MA. Reaction to LSD in a two-year-old child. J Pediatr 1972; 80:643.
  41. Gabel M, Ianzito BM. Treatment for ingestion of LSD. J Pediatr 1972; 81:634.