Hallucinogens are known for what they do to the mind, but the body goes along for the ride. Depending on the drug, physical effects can include a racing heart, higher blood pressure, dilated pupils, nausea and vomiting, sweating, shaking, poor coordination and changes in body temperature. Some hallucinogens can cause seizures, dangerously slowed breathing or fatal overheating. Nearly all of them raise the risk of accidents and injuries.
Perception, mood and long-term mental effects get their own post on how hallucinogens affect the brain. Here we stick to the physical side, starting with how these drugs get in.
How Do Hallucinogens Enter the Body?
There are several routes, and the route changes how fast effects begin:
- Swallowed. Mushrooms, LSD on paper or in liquid, MDMA pills and capsules, and mescaline-containing cacti are usually taken by mouth. The drug gets absorbed through the stomach and intestines, so effects build more slowly, often over 30 minutes to an hour or more.
- Chewed or held in the mouth. Peyote and salvia leaves can be chewed, which lets some of the drug pass through the lining of the mouth.
- Smoked or vaporized. Salvia, DMT and PCP are often smoked. Inhaled drugs reach the brain through the lungs within seconds to a minute, so the effects hit hard and fast.
- Snorted, as ketamine and MDMA powder sometimes are, which brings effects on faster than swallowing
- Injected. It’s less common, but some drugs such as ketamine are occasionally injected, which adds risks of infection and vein damage.
Whatever the route, the drug ends up in the bloodstream, travels to the brain and acts on chemical messengers that also control heart rate, temperature, breathing and muscle movement. So the body reacts right along with the mind.
Short-Term Effects of Hallucinogens on the Body
Physical effects vary by drug. The table below sums up the most common ones.
| Type | Examples | Common physical effects |
|---|---|---|
| Psychedelics | LSD, psilocybin, mescaline | Increased heart rate and blood pressure, dilated pupils, nausea and vomiting, sweating, headaches, weakness, poor coordination |
| Empathogens | MDMA (molly, ecstasy) | Raised heart rate and blood pressure, jaw clenching, nausea, sweating, dangerous overheating |
| Dissociatives | PCP, ketamine, DXM | Numbness, loss of coordination, changes in heart rate, slowed breathing at high amounts |
| Kappa opioid agonist | Salvia divinorum | Dizziness, loss of coordination, slurred speech |
| Deliriants | Datura (jimsonweed) | Very rapid heart rate, high body temperature, dry mouth, confusion |
Heart and blood pressure
Many hallucinogens, mescaline and MDMA included, raise heart rate and blood pressure. If someone has a heart problem nobody’s diagnosed, that added strain can be dangerous.
Body temperature
The DEA warns that MDMA can interfere with the body’s ability to regulate temperature, which can lead to organ failure, brain swelling and death. Deliriants can also cause severe overheating and heart failure, even in small amounts. Our facts about molly go into more detail.
Stomach and digestion
Nausea and vomiting are very common, especially with mescaline and mushrooms; the DEA calls peyote’s nausea intense. Vomiting while confused or disoriented is dangerous, more so if someone’s also been drinking. See mescaline side effects for more.
Coordination and movement
Salvia, dissociatives and high amounts of psychedelics can cause dizziness, clumsiness, slurred speech and loss of coordination. With salvia, it comes on within a minute or so of smoking. Read more about salvia divinorum effects.
Breathing and seizures
At high amounts, dissociatives such as PCP and ketamine can slow breathing, and that risk climbs when they’re combined with alcohol, opioids or other depressants. High amounts of PCP have also been linked with seizures and coma.
Accidents and Injuries: The Hidden Physical Risk
For many hallucinogens, the most common physical harm doesn’t come from the drug’s chemistry at all. It comes from what people do while their perception and judgment are bent out of shape. People on hallucinogens have walked into traffic, fallen from heights, drowned, been burned and hurt others while confused or panicked. Dissociatives add numbness, so someone can be badly injured and not notice. Driving under the influence of any hallucinogen is extremely dangerous.
Long-Term Effects on the Body
Compared with alcohol or stimulants, classic psychedelics aren’t strongly linked to organ damage. Their long-term harms tend to show up in the mind instead: hallucinogen persisting perception disorder, persistent psychosis, anxiety and depression, all covered in our brain post. Repeated use of some dissociatives has been linked with memory problems, and ketamine misuse is associated with bladder damage. Tolerance to psychedelics builds quickly too, which can push people toward larger amounts or other drugs.
Are Hallucinogens Addictive?
Depends on the drug. Classic psychedelics like LSD, psilocybin and mescaline aren’t thought to cause physical dependence, though tolerance develops fast. Dissociatives such as PCP carry more risk of compulsive use, cravings and withdrawal symptoms. And according to the National Institute on Drug Abuse, MDMA is potentially addictive.
Physical addiction is only part of it. Plenty of people come to depend on hallucinogens emotionally, using them to escape, to feel spiritual or to cope with pain. That kind of reliance can quietly reshape a life.
How Are Hallucinogens Affecting Your Life?
A few honest questions are worth asking. Are you using more often, or mixing hallucinogens with other drugs? Have you had frightening experiences and used again anyway? Are relationships, work or school slipping? Do you still notice visual changes or anxiety days or weeks after using? If the answers worry you, talk to someone.
Christian-Based Hallucinogen Treatment at Covenant Hills
Covenant Hills offers hallucinogen addiction treatment in a Christian-based residential setting in Orange County. Our residential program gives clients a safe, structured place to recover in body and mind, with faith-based and traditional tracks to choose from.
If hallucinogens are taking a toll on your health, call 800-662-2873 for a free, confidential assessment.
Frequently Asked Questions
How do hallucinogens enter the body?
They can be swallowed, chewed, smoked or vaporized, snorted or, less often, injected. Inhaled drugs act within seconds to a minute. Swallowed drugs usually take 30 minutes or longer.
What are the effects of hallucinogens on the body?
Common effects include a faster heart rate, higher blood pressure, dilated pupils, nausea, sweating and poor coordination. Some hallucinogens can also cause overheating, slowed breathing or seizures.
Can hallucinogens kill you?
Yes. Deaths have been linked to overheating (especially with MDMA), heart problems, slowed breathing with dissociatives, and accidents while intoxicated. Mixing with other drugs raises the risk.
Are hallucinogens physically addictive?
Classic psychedelics generally aren’t, though tolerance builds quickly. Dissociatives like PCP, along with MDMA, carry more risk of addiction, and psychological dependence is possible with any of them.
