Marijuana can produce depressant-like effects, but is it is a depressant?

Marijuana refers to the dried flowers and leaves of the cannabis plant. It is the most commonly used illicit drug in the United States. However, in many states, medicinal and recreational marijuana are being legalized. It is often smoked or ingested in food.

Marijuana acts similarly to alcohol in that it has both stimulant and depressant properties, according to a publication by the National Institutes of Health. Its side effects begin just as quickly but last longer than alcohol.

Many of the compounds — or cannabinoids — present in marijuana cause side effects similar to those of depressants. The National Institute on Drug Abuse and the Drug Enforcement Administration classifies marijuana as a psychoactive drug with hallucinogen effects. According to the Centers for Disease Control and Prevention, marijuana is the most widely used hallucinogen.

What Is a Psychoactive Drug?

A psychoactive drug is a chemical substance that changes a person’s brain function. This type of mind-altering medicinal or recreational substance leads to shifts in perception, mood, level of consciousness or awareness, cognitive functioning or behavior.

Marijuana falls into this category in that it can cause disorientation, unpleasant thoughts or feelings of anxiety or paranoia with chronic use, and especially in high doses. It can also affect a person’s emotions, decision-making, learning, attention, coordination, reaction time and memory. Heavy marijuana use can likewise interfere with relationships, work, school and daily functioning.

Because psychoactive drugs are rewarding, they can reinforce drug-seeking behaviors that can lead to dependence or addiction.

What Is a Depressant?

Depressants slow, or depress, the central nervous system. The central nervous system is made up of the brain and spinal cord. It is a complex network of nerves and cells called neurons that send signals or messages to different part of the body.

Depressants slow the rate at which regular activity occurs in the brain and spinal cord by slowing the rate at which the body’s nerves transmit signals by increasing the neurotransmitter gamma-aminobutyric acid.

Three main types of depressant drugs include barbiturates, benzodiazepines and sleep medications. Prescription depressant medications, such as Xanax and Valium, are intended to treat conditions such as seizures, anxiety or insomnia. These medications are helpful and generally safe when used for legitimate medical conditions and taken as prescribed.

Although marijuana can produce depressant-like effects, it is not a depressant. Instead of affecting GABA, marijuana’s sedative effects are due to the drug’s ability to increase dopamine.

A 2016 study in the journal Nature indicated that while marijuana use initially increases dopamine levels, long-term use of the drug ultimately decreases the amount of the neurotransmitter released in the brain. When dopamine levels go down, people experience the lethargy and low energy consistent with the effects of depressants.

Risks of Depressants

Risks of depressants include dependence and addiction. These risks are higher when depressants are misused. Taking these drugs to achieve a high can lead to serious and dangerous side effects.

If combined with other substances that depress the central nervous system or cause sleepiness, the outcome can be deadly. An overdose can occur, wherein a person’s heart rate and breathing can slow significantly, resulting in life-threatening consequences that require emergency medical attention.

Marijuana and Depression

Evidence to marijuana’s role in depression is lacking — specifically, whether it’s a cause or treatment. Studies have yet to definitively link marijuana use to the development of depression.

The drug’s Schedule I classification has limited scientists’ research, but some studies have shown that high doses of marijuana can worsen existing depression.

People who already suffer from depression may use marijuana to dull or numb their negative feelings. Likewise, people who use marijuana may appear to be depressed due to the drug’s depressant-like effects.

Note that the classification of a drug as a central nervous system depressant is different from the drug’s potential effect on depression. A drug that depresses your central nervous system doesn’t necessarily cause symptoms of depression, such as sadness, insomnia and loss of interest in activities unless used chronically over an extended period.

Marijuana as a Treatment for Depression

Some studies show that low doses of marijuana may help to improve depression. This finding means that marijuana’s correlation to depression is likely dose dependent.

Results of clinical research published in the Journal of Psychoactive Drugs in 2014, showed that marijuana use was associated with a decrease in symptoms of post-traumatic stress disorder (PTSD).

The sample reported an average of as much as a 75 percent reduction in all areas of PTSD symptoms. However, scientists concluded that more research was needed to account for variables.

Still, in the midst of conflicting data, the American Psychiatric Association points out that no scientific evidence exists to definitively support the use of marijuana as a viable treatment for depression or any psychiatric illness.

Related Topic: How Does Marijuana Affect Antidepressants?

If you find yourself living with marijuana addiction and co-occurring disorders like depression or anxiety, call The Recovery Village. A representative can discuss treatment options that are custom tailored to meet your specific needs. Make the call and begin treatment today.

a man with a beard wearing glasses and a hoodie.
Editor – Thomas Christiansen
With over a decade of content experience, Tom produces and edits research articles, news and blog posts produced for Advanced Recovery Systems. Read more

Bloomfield, M.A.P. et al. (2016, November 17). The effects of Δ9-tetrahydrocannabinol […]the dopamine system. 

Centers for Disease Control and Prevention. (2018, February 27). Health Effects: Marijuana: How Can It Affect Your Health? 

Centers for Disease Control and Prevention. (2018, March 7). What is marijuana?

Korem, N. & Akirav, I. (2014, June 5). Cannabinoids Prevent the Effects of a Fo[…]motional Processing.

Levine, D. (2017, August 8). Weed and Depression: Does Marijuana Make[…]or Depressed Brains?

Murray, J.B. (1986, January). Marijuana’s effect on human cognitive […]ns, and personality.

National Institute on Drug Abuse for Teens. (2017, March). Prescription Depressant Medications.

National Institute on Drug Abuse. (2018, June). Marijuana. Drug Facts.

Science Daily. (n.d.). Psychoactive drug. Reference Terms.

Stangor, C. (n.d.). 6.2 Altering Consciousness with Psychoactive Drugs.

Taylor & Francis. (2014, May 22). Cannabis effect on PTSD: Can smoking med[…]ana reduce symptoms?

Wilde, C. (2015, February 4). RIA neuroscience study points to possibl[…]uana for depression.


Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.