Effects of Hallucinogens

Hallucinogens affect a person’s perception of reality. They make people see, hear or feel things that aren’t real. The drugs also affect emotions, sleep and sexual behavior. Dissociative hallucinogens make people feel disconnected from the body.
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The hallucinogen class of drugs causes people to sense nonexistent things. The brain thinks it sees something, hears a sound, feels a sensation or smells a scent that isn’t real.

Experts think the drugs cause hallucinations by disrupting communication between chemical systems in the brain and spinal cord. These areas of the nervous system are in charge of sensory perception.

The drugs also affect parts of the brain that control other vital functions, including sleep, hunger and mood. A subclass of hallucinogens called dissociative drugs makes people feel disconnected from their body or environment.

Hallucinogen use can cause a variety of short- and long-term health effects.

The Effects of Hallucinogenic Drugs on Perception Infographic

Short-Term Effects of Hallucinogens

In addition to causing hallucinations, hallucinogens cause diverse psychoactive effects. They can make people feel relaxed, high or energetic.

Many hallucinogens also cause increased heart rate, high blood pressure and dilated pupils. Drug-specific side effects may also occur.

  • LSD can cause increased body temperature, appetite loss, numbness, weakness and tremors.
  • Psilocybin, the drug in magic mushrooms, can cause nervousness, paranoia and panic attacks.
  • Peyote’s active ingredient mescaline can cause high body temperature, coordination loss and sweating.
  • DMT can cause agitation, dizziness and muscular incoordination.

The side effects of dissociative drugs include:

  • Numbness
  • Dizziness
  • Nausea
  • Vomiting
  • High blood pressure
  • Rapid heartbeat
  • Memory loss
  • Panic
  • Paranoia
  • Aggression

Specific dissociative drugs also cause unique side effects. The effects of PCP include seizures, violent behavior and psychotic symptoms. Ketamine can cause sedation and amnesia. Salvia abuse can cause intense mood swings, including uncontrollable laughter.

Therapeutic use of dextromethorphan, a common ingredient in cough suppressants, is safe in low doses. But dextromethorphan abuse, a practice some people call robotripping, can cause

Bad Trips

People who use hallucinogens refer to their experiences with the drugs as “trips.” They call an experience that causes positive effects, such as happiness, heightened awareness and abstract thinking, a good trip.

Unpleasant side effects, such as anxiety, paranoia and panic, can lead to a bad trip. Bad trips are characterized by terrifying thoughts, loss of control and insanity.

Deaths from mescaline, mushroom or LSD overdoses are rare, according to the Drug Enforcement Administration. These drugs may increase the risk of death from dangerous behavior, accidents or suicide. High doses of PCP or ketamine can cause death.

Ketamine can cause an exceptionally bad trip called a k-hole. People who have experienced a k-hole say they felt like their consciousness disassociated from their body, according to Columbia University.

Mixing with Other Drugs

Mixing hallucinogens with other drugs can cause serious side effects. These effects depend on the type of drug, the dose and the method of use. Combining hallucinogens with stimulants, such as cocaine or amphetamines, can cause serious heart problems. Both types of drugs increase blood pressure and heart rate.

Some people mix molly and alcohol to feel more carefree. Others combine LSD and alcohol to enhance the hallucinatory effects. Mixing alcohol and MDMA can cause dangerous changes to body temperature, leading to organ damage and overdose.

Taking hallucinogens with other drugs that cause hallucinatory effects, such as marijuana, may increase the chances of having a bad trip. Hallucinations are unpredictable. Taking multiple drugs that disrupt the brain can cause serious health problems.

Long-Term Effects of Hallucinogens

Long Term Effects of Hallucinogenic Infographic

Regular use of most hallucinogens leads to tolerance. When people develop tolerance to a drug, they require higher doses to feel the same effects. However, DMT does not seem to cause tolerance, according to the National Institute on Drug Abuse.

Hallucinogens that affect the same part of the brain cause cross-tolerance. That means someone taking LSD also becomes tolerant to mescaline or psilocybin. Mescaline is the psychoactive ingredient in peyote, and psilocybin is the psychoactive drug in magic mushrooms.

Tolerance to hallucinogens usually fades quickly. Few hallucinogens produce traditional withdrawal symptoms. MDMA and PCP can be addictive and lead to uncontrollable behavior. People addicted to these drugs often need rehab to recover. Other hallucinogens do not appear to be addictive.

The short-term effects of hallucinogen use last between one and 12 hours depending on the drug. However, other effects may persist for several days or weeks.

The long-term effects of ecstasy include confusion, depression, sleep problems and cravings. The long-term effects of other hallucinogens are not fully understood. However, two conditions can be caused by the drugs.

Hallucinogen Persisting Perception Disorder (HPPD)

People who use hallucinogens sometimes have flashbacks to hallucinations experienced during a trip. Recurring flashbacks characterize hallucinogen persisting perception disorder, sometimes referred to as HPPD.

Symptoms of HPPD include:

  • Hallucinations
  • Seeing movements in peripheral vision
  • Color flashes
  • Halos around objects

The disorder is usually associated with LSD, but reports of other hallucinogens causing HPPD exist. Symptoms of HPPD sometimes improve without treatment, but medications may spur recovery from the disorder. For some, the symptoms may last for years.

Persistent Psychosis

Persistent psychosis is uncommon among people who use hallucinogens. The condition is characterized by visual hallucinations, difficulty thinking, mood problems and paranoia. Ketamine, LSD, ecstasy and salvia have reportedly caused persistent psychosis. It’s unknown if people who developed persistent psychosis were predisposed to schizophrenia or other mental illnesses.

Overall, people use hallucinogens to experience alternative realities or to think abstractly. The drugs are not associated with rates of addiction comparable to other illicit drugs. But they can cause serious short-and long-term health effects.

Medical Disclaimer: DrugRehab.com aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.

Chris Elkins, MA
Senior Content Writer, DrugRehab.com
Chris Elkins worked as a journalist for three years and was published by multiple newspapers and online publications. Since 2015, he’s written about health-related topics, interviewed addiction experts and authored stories of recovery. Chris has a master’s degree in strategic communication and a graduate certificate in health communication.

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