A type of drug, hallucinogens stem from certain plants and mushrooms, causing a change in mental state. The Palo Alto Medical Foundation notes that people have used hallucinogens for social, religious and medical purposes. Examples of common hallucinogens include PCP, LSD, peyote and psilocybin. When people use hallucinogens, they can experience different side effects—some pleasurable, others disturbing.
Hallucinations
The National Institute on Drug Abuse explains that hallucinogens cause hallucinations by disrupting serotonin, a neurotransmitter. When a person has a hallucination, she sees, hears, smells or feels things that are not really there. For example, people having a hallucination may see an animal running across the room, but no animals are in the room. The hallucinogens can cause users to feel like time has become distorted, such as everything slowing down. Users' senses can become mixed up, in which users may say they are “hearing colors.” Some users may have strange body sensations or intense sensory experiences.
The NSW Department of Health notes that during a “bad trip,” in which users have unpleasant reactions to the drugs, users can have frightening hallucinations. Users may become paranoid or feel like they are losing control. The Palo Alto Medical Foundation adds that users may experience flashbacks to the drug use, such as the hallucinations, even after discontinuing use.
Mood Changes
Hallucinogens can alter users' moods. The National Institute on Drug Abuse points out that 50 percent of people who used PCP and went to the emergency room had anxiety, in which they could not control their fears and worries. Hallucinogen use can also cause users to have mood swings. For example, users may be happy at one moment, then become sad. The NSW Department of Health adds that during a “bad trip” on a hallucinogen, users may become extremely anxious or fearful, such as believing their lives are in danger. Though rare, some users may become suicidal or violent.
Problems with Movement
Hallucinogens can cause problems with movement for users. For example, the NSW Department of Health explains that users can have poor coordination when under the influence, which can impair walking. Some people may start having tremors or muscle spasms. Other side effects include muscle weakness and numbness.
Other Physical Side Effects
People who use hallucinogens may experience other physical side effects. For example, breathing can become affected. The NSW Department of Health notes that users may breathe faster and deeper than they normally would. Heart rate and blood pressure can also increase. Users may have nausea and start vomiting. Hallucinogen use can cause dilated pupils, sweating and a dry mouth. The National Institute on Drug Abuse adds that sleepiness and a loss of appetite can occur as well.
