Side Effects of Hallucinogens
Recent studies have shed light on the physical and psychological consequences of hallucinogen use. It is important to differentiate between classical and dissociative hallucinogens, as they are associated with different side effect profiles.
Side Effects of Classical Hallucinogens
All classical hallucinogens are listed as Schedule I drugs by the DEA. This means the federal government does not recognize these drugs as having any medicinal value and considers them to have a high risk of abuse. However, mounting evidence suggests that classical hallucinogens may be beneficial in the treatment of several mental health disorders.
Short-term effects of classical hallucinogens generally set in within 20 to 90 minutes after taking the drug. These effects may last anywhere from 15 minutes to 12 hours, depending on the type of drug. Hallucinogenic drugs are associated with both positive and negative short-term side effects.
Positive short-term effects include:
- Positive Short-Term Effects of Hallucinogens
Intensified sensory perception (colors appear brighter)
Altered sense of time and space
Hallucinations (which may also be negative)
Reduced sensitivity to perceived social rejection
Increased emotional empathy
Negative short-term effects include:
Long-term effects of classical hallucinogens remain relatively unknown due to federal restrictions on research. However, in light of promising findings that suggest that classical hallucinogens may have significant therapeutic benefits, more research is being permitted.
Research that found positive long-term side effects is as follows:
- A recent study of 16 adults evaluated the long-term effects of a single dose of LSD. One year after LSD administration, those who took LSD considered the experience to be “personally meaningful” with “long-lasting subjective positive effects.” Of the participants, 10 rated the experience as “among the top 10 most meaningful experiences in their lives.” However, this study does not address the long-term effects of recreational hallucinogen use.
- A study on the long-term effects of psilocybin found that participants had increased and enduring positive changes six months after taking the drug. Larger doses of psilocybin were linked to a greater increase in positive changes, and 72% of people who took a high dose reported a significantly increased sense of well-being or life satisfaction. The same was true for 92% of people who took a high dose and also participated in regular support groups. Only 20% of the low-dose group reported a sustained increase in well-being.
- A study evaluating the effects of a single dose of psilocybin administered to cancer patients found immediate, substantial improvements in anxiety and depression. These improvements persisted for 6.5 months after administration. In addition, patients reported increased quality of life, improved attitudes toward death and reduced existential distress.
- Psilocybin-induced activation of specific serotonin receptors in the brain was shown to reduce emotional pain. In addition, it reduced self-confidence problems that are associated with social rejection and negative social interactions.
Research that found negative long-term side effects is as follows:
- A recent study evaluated the effects of hallucinogens on college students. It found that students who had used hallucinogens were more likely to have substance use disorders, mental health problems and impulsivity traits. However, this study was unable to directly attribute these outcomes to hallucinogen use. The students who reported using hallucinogens were also likely to misuse alcohol and other drugs.
- There is a potential for the development of hallucinogen persisting perception disorder (HPPD). Although it is poorly understood, HPPD is characterized by “flashbacks” that include perceptual disturbances and hallucinations. While some people report that they are not bothered by these flashback experiences, others may experience emotional distress and impairment. Evidence suggests that HPPD may be linked to pre-existing psychiatric conditions. HPPD is believed to occur in 4.2% of people who use hallucinogens.
Currently, classical hallucinogens are generally not associated with significant negative side effects when they are administered in a clinical setting. However, there is some evidence that using hallucinogens recreationally or with other drugs may increase the risk of negative long-term side effects.
Side Effects of Dissociative Hallucinogens
Dissociative hallucinogens can cause dissociation, or detachment from reality. Unlike classical hallucinogens, many dissociative hallucinogens can be prescribed or even purchased over the counter.
Dissociative hallucinogens have a wider spectrum of short- and long-term effects than classical hallucinogens. Because of this, it is difficult to describe a side effect profile that applies to all dissociative hallucinogens.
Short-term effects commonly include:
Long-term effects are quite diverse and depend on the drug that is used. Common drugs and their side effects include:
Dissociative Hallucinogens Long-Term Effects
When provided by medical professionals and taken as prescribed, ketamine can be an effective antidepressant drug for people with treatment-resistant depression. However, chronic ketamine misuse can lead to dependence and addiction. It can also impair learning and memory, cause severe and widespread brain damage and cause liver, kidney and bladder injury.
- Dextromethorphan (DXM)
DXM is the active ingredient in many over-the-counter cough syrup formulations. Some data suggests that DXM can have positive effects on depression, pain, Parkinson’s disease, and other conditions. Unfortunately, some teens will consume an entire bottle of cough syrup in one sitting to experience the hallucinogenic effects of DXM. This puts them at risk for DXM toxicity and can lead to psychosis, respiratory depression, seizures, coma, and even death. In addition, DXM is often consumed with alcohol, which significantly increases the risks of overdose.
- Phencyclidine (PCP)
PCP was used as a general anesthetic in the 1950s, but its use was discontinued due to the hallucinogenic effects that followed. PCP has become a popular recreational drug, but it is associated with very serious negative consequences. These side effects include mild to severe agitation, delusions, violent behavior, seizures, coma, and death. In addition, some evidence suggests that PCP can induce the onset of schizophrenia.
Side Effects of Polysubstance Abuse
Polysubstance abuse is defined as the simultaneous misuse of more than one drug. Common drugs that are misused with hallucinogens include alcohol, cocaine, marijuana, opioids, and amphetamines.
Polydrug abuse may significantly increase the likelihood of negative outcomes. It can lead to someone experiencing a “bad trip” (scary hallucinations, paranoia, the feeling that the trip will never end) and can encourage erratic and dangerous behavior. Polysubstance abuse with dissociative hallucinogens increases the risk of an overdose.