Does Cannabis Cause Hallucinations?


Cannabis, commonly known as marijuana, consists of the dried leaves, stems, flowers and seeds from the cannabis indica plant. It is the most preferred and widely available illicit drug in the world. As a result, it is also highly abused. Cannabis is also used in medical treatments. CBD (cannabidiol) and THC (tetrahydrocannabinol) are the two prime components of cannabis, and both components have different properties.

When it comes to recreational use, cannabis is consumed in various forms in different spheres of life. Different methods of consuming cannabis also lead to varied effects. To find an honest and complete answer to the question ‘Does Cannabis cause hallucinations?’, it is necessary to define and understand various facts about the drug in detail. This article has been divided into sections that look into the finer aspects of the composition and consumption of cannabis.


Usage of Cannabis

Historically, cannabis has been used for medical, recreational and spiritual purposes. The following points look at each of the uses in detail.

For Medical Purposes

Medically, cannabis is currently being used for many serious and general ailments. Medical cannabis is touted as the perfect alternative to opioids because opioids are well known to cause alarming death rates. Medical cannabis, on the other hand, achieves similar results of reducing nausea from chemotherapy and treating anxiety and depression without being fatal.

CBD (cannabidiol) is also another form of cannabis that is widely used for health purposes. Unlike THC (tetrahydrocannabinol), which has a psychoactive effect, CBD has a calming and relieving effect and is used for creating treatments to reduce pain and mental anxiety. Upon consumption of CBD, the receptors activated in the brain are quite different compared to THC and hallucinogenic drugs.

Hallucinations, however rare, can happen due to medical cannabis, but they are most likely owing to other factors such as consuming high levels of THC before developing tolerance, history of psychotic illness, or combining the treatment with other hallucinogenic drugs. Medical practitioners prescribe cannabis after careful examination and valuation, but it does have side effects. Apart from rare hallucinations, the most common side effects include feeling tired, dizziness and vomiting.

For Recreational Purposes

Cannabis, on consumption, generates psychoactive and physiological effects in the body. This is what is known as a ‘high’. Depending on various factors as the strain of cannabis used and type of usage, the immediate effects of consuming cannabis include:

  • Feelings of relaxation and euphoria
  • Heightened awareness of various sensations in the immediate environment
  • Increased sex drive and stamina
  • Distorted perceptions of space and time
  • Change in the conscious perception of one’s immediate vicinity

When consumed at higher doses, especially when one is yet to develop the tolerance for it, the effects of cannabis can include:

  • Changed body image.
  • Illusions of auditory and/or visual nature.
  • Pseudo hallucinations.
  • Loss of coordination and muscle control from selective impairment of reflexes.

In certain grave cases, cannabis can lead to states of dissociation, including derealization and depersonalization.

Immediate side effects of cannabis usage can also include:

  • Reduced short-term working memory.
  • Feelings of dryness in the mouth.
  • Impaired and reduced motor skills and red eyes.

In addition to changing the perception and mood of the user, other short-term neurological and physical side effects are an increase in heart rate, changed appetite and unusual changes in how one consumes food, reduced blood pressure, and lack of concentration.

Some users have also reported experiencing acute psychosis. This is not a long term effect and usually abates after a few hours. In rare cases, heavy users of the drug may find themselves experiencing these episodes for many days. Heavy cannabis use is generally associated with a reduced quality of life. However, this relationship is not quite consistent and weaker than what has been seen in the case of heavy tobacco and alcohol abusers.

For Spiritual Purposes

Historically, cannabis holds a sacred status among several religions in the world. It has served the purpose of an entheogen – a psychoactive substance used for religious, shamanic, or spiritual purposes to alter consciousness – in the Indian subcontinent since the Vedic period dating back to approximately 1500 BCE. In Greek mythology, too, there are several references to a potent drug that was used to eliminate anguish and sorrow.

Herodotus’s written records point to Scythian ceremonial practices involving the drug, especially the periods of 5th and 2nd century BCE. In modern times, cannabis has been used for spiritual purposes by several spiritual groups, like the Rastafari movement disciples. They use cannabis as an aid to their meditation and a sacrament. In the Indian subcontinent, the earliest known reports regarding cannabis having a sacred status have been attributed to the Atharva Veda, which was composed around 1400 BCE.

Effects of Cannabis

On smoking cannabis, THC and other psychoactive chemicals from the herb first go to the lungs, then into the bloodstream, and finally travel through the body to the brain. The effects of THC vary dramatically for each person but are felt almost instantly. The effects are considerably delayed and lesser if consumed by way of eating or drinking, as the digestive system takes time to transmit to the brain. Delayed and lesser effects often lead the consumer to take large doses for want of a higher kick.

Though THC may be detected in the body even weeks after the use of cannabis, its noticeable effects generally last for up to three hours if smoked and many hours if eaten or drunk. The experience ranges from pleasant feelings of euphoria and relaxation to a heightening of sensory perception, bursts of laughter, modified perception of time, and an increase in appetite. Though not universal in nature, the experiences of consuming marijuana vary for each person.

Unpleasant experiences may include feeling fear, distrust, anxiety or panic instead of relaxation and euphoria. The inexperience of the person or high potency of marijuana or frequent consumption makes the recurrence of unpleasant effects more common. Acute psychosis, which can include delusions and hallucinations, is also experienced when large doses are consumed. These reactions are temporary in nature and distinct from psychotic disorders.

Types of Hallucinations

Hallucination, a Latin word that means ‘to wander mentally’, is the perception of seeing or hearing something that really does not exist. This occurs most commonly because of mental illness but is common even under the influence of a drug. Hallucinations can affect one’s vision, taste, sense of smell, hearing, or even bodily sensations. Hallucinations can largely be classified into five categories: visual, olfactory, gustatory, auditory and tactile.

The most common mental illnesses that can cause hallucinations include Alzheimer’s disease, various forms of dementia, especially Lewy body dementia, Parkinson’s disease, Charles Bonnet syndrome, migraines, schizophrenia, brain tumor and epilepsy. The hallucinations caused by these illnesses can be debilitating in nature, long term, and very frequent, especially unmedicated. These hallucinations can affect various parts of the human body, such as the eyes, nose, tongue and brain.

Apart from mental illnesses, abuse of various psychoactive substances is another fairly common cause of hallucinations. Drinking large amounts of alcohol or consuming illicit drugs such as cocaine, heroin, marijuana (cannabis), and MDMA (ecstasy/molly) in high dosage can also lead to strong hallucinations among users. Hallucinogenic drugs such as LSD and PCP are also the cause of hallucinations, as is evident from the category of the drugs.

Risks Associated with Cannabis

Cannabis is one of the most preferred and widely available drugs from the ones listed above. It is an illicit drug that is widely used in the US and the world. Increasing consumption by the general public and youth in particular show significant evidence for cannabis being related to mental illness. Insufficient knowledge of both the detrimental and therapeutic effects of cannabis can lead to possible catastrophic results.

Regular usage of cannabis to get high can affect one’s mental health too. Unpleasant experiences with marijuana can leave one anxious, panicked and afraid. Distorted thinking, chances of addiction, impaired brain function, damaged lungs, weak heart and irregular diet are some of the common ways that cannabis consumption can affect mental health and cause serious and life-altering complications, especially among young adults.

Cannabis and Hallucinations

As one of the world’s most abused substances, the frequent use of cannabis and its impact on the schizophrenia spectrum commands special attention. If its usage is started at a young age, the risk of developing schizophrenia is doubled in the future. The risk of developing psychotic illnesses, including hallucinations and delusions, increases manifold if marijuana is consumed daily.

Cannabis-induced psychosis (CIP), a variety of other psychiatric conditions and cannabis consumption are strongly correlated through numerous pieces of evidence. CIP, owing to its distinguishing characteristics, is quite hard to differentiate from other kinds of psychoses. The increased push for legalizing cannabis from various advocacy groups makes it critical to assess CIP in time and research treatments for the future.


From the information above, it can be concluded that cannabis does cause hallucinations. The probabilities are lesser in the case of medical usage and quite high in the case of recreational use, especially if the user is inexperienced in the amount or dosage to take. However, the widespread use of the psychoactive herb for medical, recreational, and spiritual purposes only makes it more urgent to raise awareness about it. People taking it for recreational purposes need to be equipped to use it responsibly to avoid complications.