Psychedelic drugs are famous for causing hallucinations—they make you see, hear, taste, smell, or touch things that aren’t actually there.
Psychedelic hallucinations vary a great deal. They depend on the psychedelic drug you take, as well as the dosage, your mindset, and the environment in which you trip. You also may not experience them at all, especially at lower doses.
Here’s a look at why psychedelic hallucinations happen, how they can differ, and what it’s like to experience one.
What are Hallucinations?
A hallucination is when you perceive something in your environment that isn’t actually there. Hallucinations vary in intensity and duration. They can happen through any of the five senses, and they can range from wonderful to terrifying.
Hallucinations happen for a variety of reasons. They may be the result of diseases—such as Alzheimer’s or other types of dementia—or mental disorders like schizophrenia. In some cases, brain damage may cause hallucinations as well, particularly as a result of a stroke or seizure. In the above cases, hallucinations are generally long-lasting.
You may also experience temporary hallucinations after taking a psychedelic drug (appropriately, psychedelics are also called hallucinogens). These hallucinations only last for the duration of the drug’s effect; once the drug wears off, you return to reality.
How do psychedelic hallucinations and sensory distortions differ?
True hallucinations involve perceiving something that isn’t there—for example, closing your eyes and, in complete darkness, seeing an elephant walking toward you, or hearing a voice while you’re in a room alone. With a hallucination, your mind is fabricating an experience that does not exist in the physical world.
You may experience true hallucinations when you take a higher dose of a psychedelic drug.
At lower doses, however, it’s more common to have sensory distortions—altered perceptions of things that really do exist. For example, it’s common to see inanimate objects “breathe ” while on psychedelics; they expand and contract as if they’re inhaling and exhaling. Colors may seem brighter, and objects may leave trailing duplicates of themselves as they move. You may also experience sounds differently—someone talking right next to you may sound far away, or vice versa.
These are all examples of sensory distortions. They aren’t hallucinations; they’re altered perceptions of things that really do exist.
Types of Psychedelic Hallucinations
Hallucinations can span all five senses. Psychedelics most commonly produce visual and auditory hallucinations—that is, they make you see and hear things that aren’t there. 1 Limited research suggests that tactile hallucinations are also somewhat common while on psychedelics, while hallucinations involving taste and smell seem to be rare. 2,3
Visual hallucinations are fairly common with psychedelic drugs and tend to become more intense as dose increases. 1 At lower doses, you’re more likely to experience visual distortions, not full-on hallucinations.
During a psychedelic trip, visual hallucinations and distortions may include:
- Nonexistent people, beings, or objects
- Halos or auras around things in your environment
- Enhanced colors
- Colorful geometric patterns that appear when you close your eyes, or that inhabit the surfaces of objects
- Walls that look like they’re breathing
- Visual warping—a hallway, for example, may appear longer or shorter than it actually is
- Alice In Wonderland Syndrome—seeing yourself as giant or tiny relative to your surroundings 4
- Tracers—opaque trails that follow objects as they move, like the ones you see in long-exposure photography
Auditory (sound-based) hallucinations are also common during psychedelic trips. 1 They may include:
- Nonexistent people or other entities speaking
- Hearing music
- Sounds that are appropriate for your environment, but aren’t real (for example, knocking at your door when nobody is actually there)
- Sounds that would never naturally occur in your environment
- Receiving messages or insights (especially common during psychedelic-induced mystical experiences)
- Altered sense of auditory distance (for example, someone next to you sounds far away)
Tactile hallucinations involve perceiving a convincing physical sensation that isn’t real.
In the context of psychedelics, touch-based hallucinations are less common than visual or auditory hallucinations. 3 However, they do occur occasionally, especially during mystical encounters, during which you have the sensation of interacting with otherworldly beings. 2
Tactile hallucinations aren’t well-reported in scientific research. However, anecdotal examples include:
- Feelings or vibrations across your skin
- Physical interactions with spirits, angels, gods, or other supernatural entities 2
- Changes in temperature (warmth or cold)
- Tactile synesthesia—the ability to experience physical sensations in response to abstract thoughts. For example, thinking about your hand being cold and then feeling cold on your hand
Gustatory and olfactory hallucinations
Gustatory (taste-based) and olfactory (smell-based) hallucinations are both very rare during psychedelic experiences, with virtually no examples cited in the scientific literature.
Taste and smell hallucinations are more common as a result of strokes or seizures. 5
Psychedelics can also cause alterations in the way you perceive time (called chronoceptive hallucinations). You may experience time as speeding up or slowing down. In some cases, time may seem to stop for a few moments, then accelerate to “catch up” to the normal passage of time.
Some people report that a DMT session feels like hours or even days, when the trip lasts 10-30 minutes.
What Causes Psychedelic Hallucinations?
Classical psychedelics work by turning on your brain’s 5HT2A receptors—a type of serotonin receptor that influences sensory perception.
We don’t yet fully understand how psychedelics affect 5HT2A receptors. However, early research suggests that psychedelic drugs alter the visual, auditory, and tactile centers of your brain, causing hallucinations. 6,7
In addition, researchers have found that if you block 5HT2A receptor activity and then give someone a psychedelic, that person won’t experience hallucinations—suggesting that 5HT2A receptors are the key to psychedelics’ hallucinogenic effects. 7
Psychedelic Hallucination Frequently Asked Questions
What is an example of a hallucination?
A hallucination is when you perceive something that doesn’t actually exist. Hallucinations can happen through any of your five senses. Examples would be hearing a voice while you’re in a quiet room alone, or closing your eyes and seeing colorful geometric patterns.
What does a psychedelic hallucination feel like?
Hallucinations change from person to person and trip to trip. They can range from pleasant to frightening. They also vary in intensity. For example, you may hear a gentle ticking sound and know it’s a hallucination. Alternatively, you may meet an otherworldly being that seems completely real.
How long can psychedelic hallucinations last?
Psychedelic hallucinations only last for the duration of the drug’s effect. The total time varies depending on the psychedelic. It may be around 4-6 hours for psilocybin mushrooms and closer to 12 hours for LSD (acid). Hallucinations usually peak in intensity toward the middle of the trip, then taper off.
Why do psychedelic hallucinations happen?
Psychedelic drugs activate your brain’s 5HT2A receptors—a special class of serotonin receptors that influence sensory perception. We still don’t fully understand how psychedelics affect brain function. However, early research suggests that psychedelic drugs alter 5HT2A activity in the visual, auditory, and tactile centers of your brain, causing hallucinations.
Hallucinations are one of the hallmark effects of psychedelic drugs. They can affect any of your five senses, although they’re usually either visual, auditory, or tactile (touch-based).
Hallucinations can be frightening, or they can be enjoyable. They come in many different forms and vary in scope. You may see slightly brighter colors, or you may meet otherworldly beings who seem more real than your daily reality.
Whatever form psychedelic hallucinations take, one thing is constant: they’re usually intense experiences. If you’re planning to take a psychedelic, we recommend preparing for the experience and learning how to do integration afterward.
2. Griffiths RR, Hurwitz ES, Davis AK, Johnson MW, Jesse R. Survey of subjective “God encounter experiences”: Comparisons among naturally occurring experiences and those occasioned by the classic psychedelics psilocybin, LSD, ayahuasca, or DMT. PLoS ONE. 2019;14(4):e0214377. doi:10.1371/journal.pone.0214377
3. Leptourgos P, Fortier-Davy M, Carhart-Harris R, et al. Hallucinations under psychedelics and in the schizophrenia spectrum: an interdisciplinary and multiscale comparison. Schizophr Bull. 2020;46(6):1396-1408. doi:10.1093/schbul/sbaa117
6. Kometer M, Cahn BR, Andel D, Carter OL, Vollenweider FX. The 5-HT2A/1A agonist psilocybin disrupts modal object completion associated with visual hallucinations. Biol Psychiatry. 2011;69(5):399-406. doi:10.1016/j.biopsych.2010.10.002