Is Marijuana a Depressant?

Step by step on rolling a joint.

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Marijuana is a psychoactive drug that can affect people in different ways. While it may act as a depressant for some, it can be a stimulant for others. Learn more about what marijuana is, its short- and long-term effects, and how it may affect those who use it.

Most Important Things to Know About Marijuana

  • Marijuana affects different people in different ways, making it impossible to predict how it will affect you.
  • Marijuana use is associated with negative short- and long-term effects, ranging from mood swings to increased heart attack risk.
  • Research concerning the use of marijuana for mental health treatment is in its early stages, making it unclear as to whether the drug is safe or effective for these purposes.

What Is Marijuana?

Marijuana is a drug made out of the dried leaves and buds of a plant called Cannabis sativa. It’s also casually referred to as grass, weed, herb, and Mary Jane. Marijuana can be smoked, consumed as a tea, or combined with certain foods such as cookies to make edibles. 

Marijuana is a recreational drug that is legal in some areas of the world and illegal in others. While it remains illegal in many countries, there has been a shift in the United States over the last couple of decades. Many states have legalized the recreational and medicinal use of marijuana, and it can be bought at local dispensaries in some states.

Marijuana is made up of several chemicals called cannabinoids. The two most recognizable cannabinoids are delta-9-tetrahydrocannabinol (THC)  and cannabidiol (CBD). THC is the main active ingredient in marijuana and is responsible for the psychoactive effect you feel when using the drug. 

Marijuana as a Depressant

There have been decades of research into how marijuana affects the human body. However, it’s still not clearly understood how exactly it works.

While marijuana can have a depressant effect, it’s not technically a depressant. The effects of marijuana are wide-ranged and individualistic. While some people might experience depressant effects while using marijuana, others might not.

Factors such as the way it’s consumed and which strain is consumed come into play when considering whether marijuana will act as a depressant or not. 

What Is a Depressant?

To understand marijuana’s depressant qualities, you must first understand how a depressant affects the mind. A depressant is a drug that slows brain activity. The most common depressants include benzodiazepines, barbiturates, and sleep medications.

Like with other types of drugs, depressants are not without adverse effects. A depressant could cause side effects such as:

  • Difficulty concentrating
  • Dizziness
  • Confusion
  • Headaches
  • Memory problems
  • Slurred speech

Marijuana Use for Mental Health Conditions

It's important to stress that research involving the use of marijuana for mental health is in its very early stages. This makes it unclear as to whether this drug is effective or safe to use for certain mental health disorders.

For example, the link between depression and marijuana is often discussed, whether as a cause or treatment. However, there isn’t sufficient evidence to back either claim. Additionally, some research shows that the depressant effects of marijuana could worsen depression symptoms.

In regard to the drug's safety, studies show that combining marijuana with other drugs can be harmful, even those that are prescribed. Some of the drugs that marijuana can interact with include warfarin, clobazam, and central nervous system depressants such as alcohol, barbiturates, and benzodiazepines.

As of February 2023, the U.S. Food and Drug Administration (FDA) has not approved any cannabis-containing drugs for use in the treatment of mental health issues.

Effects of Marijuana Use

Marijuana use can lead to both short- and long-term effects.

Short-Term Effects

The most common short-term effects of marijuana use include: 

  • Altered senses, i.e., seeing colors more vividly or hearing music more loudly
  • Difficulty thinking
  • Feeling an altered sense of time
  • Memory impairment 
  • Mood swings 

When smoked, the effects of marijuana are more immediate. However, when ingested, the effects can take several minutes to hours to appear due to the drug having to pass through the digestive system first. Marijuana's effects also last longer when ingested.

Long-Term Effects 

More research needs to be done to identify the long-term impact of marijuana, with some proof that it could result in lasting effects such as: 

  • Respiratory problems: Smoking marijuana regularly could irritate your lungs. In a 2014 study, researchers found that smoking marijuana habitually was linked to an increased risk of developing chronic bronchitis.
  • Increased heart attack and stroke risk: When using marijuana, your heart rate spikes. This could increase your risk of having a heart attack or stroke, also potentially increasing your risk of a heart or vascular disease.
  • Pregnancy-related risks: Research shows that marijuana use during pregnancy isn’t safe for the fetus. Studies show that it could cause brain development problems, low birth weight, premature birth, or an increased risk of stillbirth. 
  • Brain health: Many studies suggest a long-term effect of marijuana on the brain. In a 2014 study, researchers found that marijuana use could affect neural connectivity in parts of the brain that carry out memory and learning functions. A 2022 study found that long-term use is connected to cognitive deficits and decreased hippocampal volume in mid-life.

If you use marijuana and experience worrying side effects, please visit your nearest emergency room.

Can Marijuana Be a Stimulant or Hallucinogen?

In addition to having depressant effects, marijuana could also act as a stimulant or hallucinogen. Again, factors such as how it is consumed, which strain is used, and how much is consumed come into play. 

Stimulant Effects

Stimulants are psychoactive drugs that increase brain activity, similar to what one would experience while in a manic state. They cause a disruption in the normal communication which typically occurs in the brain's neurons and circuits.

Marijuana sometimes has stimulant effects and research has found that the more a person anticipates these effects, the heavier and more frequent their marijuana use. This type of use can potentially lead to marijuana dependency and addiction

If you or a loved one are struggling with substance use or addiction, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area. 

For more mental health resources, see our National Helpline Database.

Stimulants are also associated with certain side effects. Some side effects one might experience when taking stimulants include increased anxiety, nausea, tremors, and seizures. 

Hallucinogenic Effects

Hallucinogens are drugs that are capable of altering the way you view reality. For example, when using a hallucinogen, you might hear or see things that aren’t there. Although rare, marijuana can cause mild hallucinogenic effects. 

Summary

Marijuana use is associated with negative effects, both short- and long-term. It's also unclear as to whether this drug is safe or effective for treating mental health disorders. Your healthcare provider can help you find treatment options that have been more thoroughly vetted for your mental health condition, helping you feel better without risking your mental or physical health.

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Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Toketemu Ohwovoriole
Toketemu has been multimedia storyteller for the last four years. Her expertise focuses primarily on mental wellness and women’s health topics.