Addiction Drug Use Hallucinogens Flashbacks Disorder When Taking Acid By Elizabeth Hartney, BSc, MSc, MA, PhD Elizabeth Hartney, BSc, MSc, MA, PhD Elizabeth Hartney, BSc, MSc, MA, PhD is a psychologist, professor, and Director of the Centre for Health Leadership and Research at Royal Roads University, Canada. Learn about our editorial process Updated on November 27, 2020 Medically reviewed Verywell Mind articles are reviewed by board-certified physicians and mental healthcare professionals. Medical Reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by John C. Umhau, MD, MPH, CPE Medically reviewed by John C. Umhau, MD, MPH, CPE John C. Umhau, MD, MPH, CPE is board-certified in addiction medicine and preventative medicine. He is the medical director at Alcohol Recovery Medicine. For over 20 years Dr. Umhau was a senior clinical investigator at the National Institute on Alcohol Abuse and Alcoholism of the National Institutes of Health (NIH). Learn about our Medical Review Board Print Jovana Milanko/Stocksy United Table of Contents View All Table of Contents Background Duration Other Causes While research suggests that the phenomenon is rare, "acid flashbacks" are more than a memory for some people who have used acid or other hallucinogenic drugs such as phencyclidine (PCP). The Facts About LSD While these drug-related hallucinations can be unpleasant and distressing, they are usually temporary. If they do persist, flashbacks can be difficult to cope with and can disrupt a person's everyday life. In some cases, flashbacks can be a sign of an underlying mental health disorder or medical condition. The good news is, these causes can be treated as long as they are properly diagnosed. The Short and Longterm Effects of Hallucinogens What Are Flashbacks? Flashbacks are a type of disturbed perception or distorted sensory experience that affects your senses; how you see, hear, feel, taste, or smell the things around you. Unlike memories (which are distant ideas that you know are not happening in the present) flashbacks seem as if they are actually happening in the current moment. The "realness" of flashbacks from a drug can be so intense that someone may think they must have taken the drug again, or that they are experiencing a mental health crisis (they may fear they are "losing their mind"). Most of the time, someone having a flashback is aware that what is happening at the moment is not real. They know that what they are experiencing is related to a drug they took in the past and that they have not taken the drug again in the present. Why People Take Hallucinogens If their experience was pleasant, a flashback can cause someone to re-experience the euphoria they got from taking the drug. However, pleasant flashbacks can also be problematic. For example, someone who is experiencing an amusing flashback in public runs the risk of laughing in a socially inappropriate situation such as a funeral. These experiences can be embarrassing and distressing for the person having the flashback as well as for those around them. How Psychedelic or Hallucinogenic Drugs Work Hallucinogen Persisting Perception Disorder (HPPD) If someone has flashbacks that cause significant distress or feel uncontrollable, they may have Hallucinogen Persisting Perception Disorder (HPPD). The diagnosis has specific criteria laid out in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Symptoms of HPPD include: AfterimagesFalse perceptions of movement out of the corner of the eye (peripheral vision)Flashes of colorHallucinations (especially of geometric forms)Halos around objectsInanimate objects appearing alive (for example, walls that appear to be "breathing" or growing)Intensified colorObjects appearing larger than they are (macropsia)Objects appearing smaller than they are (micropsia)Trails of images of moving objects What Causes HPPD? How Long Do Flashbacks Last? Most of the time, flashbacks related to using drugs only last for a few minutes and do not cause significant distress. The person is fully aware of what's happening and realizes that they are experiencing a hallucination. Flashbacks can last for minutes, hours, weeks, months, or years. Flashbacks may occur in episodes, meaning that a person feels normal most of the time and has occasional flashbacks that come on suddenly or unpredictably. Some people find that visual disturbances can even be triggered simply by remembering a time that they took a drug that caused them to hallucinate. In others, flashbacks can be continuous. A person's distress levels will depend on the nature and content of the hallucinations as well as how they feel about the experience (which is especially influenced by anxiety, depression, or paranoia). What Are Flashbacks Like? Some flashbacks are pleasant, like looking up at the sky and seeing the vivid and intense shades of blue, perhaps with some calming, swirly, cloud patterns. However, these visuals can also be highly distressing—for example, imagine how you would feel if you had a fear of spiders and constantly saw them all around you (or even on you). The Different Kinds of Hallucinations Other Causes of Flashbacks People who experience flashbacks may find that the visuals either go away on their own or become easier to control over time as they adjust to the experience. However, some people find the perceptual disturbances overwhelming and difficult to manage. Flashbacks can have a significant impact on a person's life, such as by making it difficult for them to go to school or work. In some cases, the visual disturbances that a person assumes are "acid flashbacks" might be a sign of an undiagnosed mental health problem. People who have certain mental health conditions such as substance-induced psychosis, schizophrenia, and post-traumatic stress disorder (PTSD), can also experience flashbacks. Flashbacks in PTSD In some cases, flashbacks are caused by an underlying physical condition such as migraines, brain lesions, or a seizure disorder. Specific disturbances in one or more senses (sight, hearing, taste, smell, and touch) can be brought on by eye conditions, neurological diseases, hearing problems, and stroke. If you are experiencing hallucinations, getting a timely and accurate diagnosis is crucial. While most of the physical and mental health conditions that can cause hallucinations, (including drug use) can be managed or treated, some can have serious consequences if left untreated. A Word From Verywell People who experience flashbacks may feel a great deal of distress and even fear that they are losing touch with reality. However, it's important to know that many of the conditions that can cause these visual disturbances—including drug use—are treatable. If you are experiencing flashbacks, whether or not you have taken LSD or another drug, talk to your doctor. They may refer you to a psychiatrist or an American Board of Addiction Medicine (ABAM) certified physician. These professionals can figure out what is causing your flashbacks, prescribe the appropriate treatment, and make sure you have access to resources, support, and tools to help you cope. When Does Drug Use Become Addiction? 6 Sources Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Krebs TS, Johansen P-Ø. Psychedelics and Mental Health: A Population Study. PLoS ONE. 2013;8(8):e63972. doi:10.1371/journal.pone.0063972 Halpern JH, Lerner AG, Passie T. A Review of Hallucinogen Persisting Perception Disorder (HPPD) and an Exploratory Study of Subjects Claiming Symptoms of HPPD. Curr Top Behav Neurosci. 2018;36:333-360. doi:10.1007/7854_2016_457 Lerner AG, Rudinski D, Bor O, Goodman C. Flashbacks and HPPD: A Clinical-oriented Concise Review. Isr J Psychiatry Relat Sci. 2014;51(4):296-301. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th edition. Washington, DC; 2013. Lerner AG, Goodman C, Rudinski D, Lev-Ran S. LSD Flashbacks - The Appearance of New Visual Imagery Not Experienced During Initial Intoxication: Two Case Reports. Isr J Psychiatry Relat Sci. 2014;51(4):307-309. Krebs TS, Johansen PØ. Psychedelics and Mental Health: A Population Study. PLoS ONE. 2013;8(8):e63972. doi:10.1371/journal.pone.0063972 Additional Reading Hermle L, Ruchsow M, Täschner KL. [Hallucinogen Persisting Perception Disorder (HPPD) and Flashback Phenomena – Differential Diagnosis and Explanation Models]. Fortschr Neurol Psychiatr. 2015;83(9):506-515. doi:10.1055/s-0035-1553717 Orsolini L, Papanti GD, De Berardis D, Guirguis A, Corkery JM, Schifano F. The "Endless Trip" among the NPS Users: Psychopathology and Psychopharmacology in the Hallucinogen-Persisting Perception Disorder. A Systematic Review. Front Psychiatry. 2017;8:240. doi:10.3389/fpsyt.2017.00240 By Elizabeth Hartney, BSc, MSc, MA, PhD Elizabeth Hartney, BSc, MSc, MA, PhD is a psychologist, professor, and Director of the Centre for Health Leadership and Research at Royal Roads University, Canada. See Our Editorial Process Meet Our Review Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit Get Treatment for Addiction Advertiser Disclosure × The offers that appear in this table are from partnerships from which Verywell Mind receives compensation.