Hallucinogens are a group of drugs that change a person’s awareness of their surroundings, thoughts, and feelings. Hallucinogens can cause hallucinations—sensations and images that seem real even though they aren’t.

(By the way, classifying drugs into categories isn’t a perfect science, because drugs can have several different effects. For example, some drugs not technically classified as hallucinogens can also cause hallucinations, including bath salts, marijuana or weed, and Spice.)

Some hallucinogens come from plants or mushrooms, and others are synthetic (human-made). Depending on the drug, hallucinogens may be swallowed as pills, snorted, brewed in tea, or consumed in other ways.

According to the 2019 Monitoring the Future survey, few teens are using hallucinogens, and the percentage of teens who said they’d used hallucinogens in the previous year was about the same as in 2018. That’s good, because hallucinogens’ effects can be unpredictable.

They’re divided into two categories: classic hallucinogens and dissociative drugs.

Classic hallucinogens

These include:

• LSD (sometimes called acid, blotter acid, or dots).
• Psilocybin (magic mushrooms, shrooms).
• Peyote or mescaline (buttons, cactus, or mesc).
• DMT (Dmitri).
• 251-NBOMe (N Bomb or 251).

The effects of classic hallucinogens can include increased blood pressure, sleep problems, panic, paranoia (extreme and unreasonable distrust of other people), psychosis (thinking that is detached from reality), and many others.

Sometimes, using classic hallucinogens can lead to long-term psychosis. This happens more often in people who have a history of mental disorders, but it can happen to anybody—even after they use hallucinogens once.