Marijuana: Side Effects, Hazards & Treatment

What is marijuana?

Marijuana refers to the dried leaves, flowers, stems, and seeds from the Cannabis sativa or Cannabis indica plant. The plant contains the mind-altering chemical THC and other similar compounds. Extracts can also be made from the cannabis plant.

Marijuana is the most commonly used illicit drug in the United States.1 Its use is widespread among young people. In 2015, more than 11 million young adults ages 18 to 25 used marijuana in the past year.

According to the Monitoring the Future survey, rates of marijuana use among middle and high school students have dropped or leveled off in the past few years after several years of increase. However, the number of young people who believe regular marijuana use is risky is decreasing.

People smoke marijuana in hand-rolled cigarettes (joints) or in pipes or water pipes (bongs). They also smoke it in blunts—emptied cigars that have been partly or completely refilled with marijuana. To avoid inhaling smoke, some people are using vaporizers.

These devices pull the active ingredients (including THC) from the marijuana and collect their vapor in a storage unit. A person then inhales the vapor, not the smoke. Some vaporizers use a liquid marijuana extract.

What are the short-term effects of marijuana?

When a person smokes marijuana, THC quickly passes from the lungs into the bloodstream. The blood carries the chemical to the brain and other organs throughout the body. The body absorbs THC more slowly when the person eats or drinks it. In that case, they generally feel the effects after 30 minutes to 1 hour.

THC acts on specific brain cell receptors that ordinarily react to natural THC-like chemicals. These natural chemicals play a role in normal brain development and function.

Marijuana overactivates parts of the brain that contain the highest number of these receptors. This causes the “high” that people feel. Other effects include:

  • Altered senses (for example, seeing brighter colors)
  • Altered sense of time
  • Changes in mood
  • Impaired body movement
  • Difficulty with thinking and problem-solving
  • Impaired memory
  • Hallucinations (when taken in high doses)
  • Delusions (when taken in high doses)
  • Psychosis (when taken in high doses)

What are the long-term effects of marijuana?

Marijuana also affects brain development. When people begin using marijuana as teenagers, the drug may impair thinking, memory, and learning functions and affect how the brain builds connections between the areas necessary for these functions.

Researchers are still studying how long marijuana’s effects last and whether some changes may be permanent.

What are the other health effects of marijuana?

Marijuana use may have a wide range of effects, both physical and mental.

Physical effects of marijuana

  • Breathing problems
  • Increased heart rate
  • Problems with child development during and after pregnancy
  • Intense Nausea and Vomiting

Mental effects of marijuana

Long-term marijuana use has been linked to mental illness in some people, such as:

  • Temporary hallucinations
  • Temporary paranoia
  • Worsening symptoms in patients with schizophrenia—a severe mental disorder with symptoms such as hallucinations, paranoia, and disorganized thinking

Are there effects of inhaling secondhand marijuana smoke?

Studies have shown that people who don’t use marijuana report only mild effects of the drug from a nearby smoker, under extreme conditions.

More research is needed to know if secondhand marijuana smoke has similar health risks as secondhand tobacco smoke. A recent study on rats suggests that secondhand marijuana smoke can do as much damage to the heart and blood vessels as secondhand tobacco smoke.

But researchers haven’t fully explored the effect of secondhand marijuana smoke on humans. What they do know is that the toxins and tar found in marijuana smoke could affect vulnerable people, such as children or people with asthma.

Is marijuana a gateway drug?

Animal studies have shown that early exposure to addictive substances, including THC, may change how the brain responds to other drugs.

For example, when rodents are repeatedly exposed to THC when they’re young, they later show an enhanced response to other addictive substances—such as morphine or nicotine—in the areas of the brain that control reward, and they’re more likely to show addiction-like behaviors.

Although these findings support the idea of marijuana as a “gateway drug,” the majority of people who use marijuana don’t go on to use other “harder” drugs.

It’s also important to note that other factors besides biological mechanisms, such as a person’s social environment, are also critical in a person’s risk for drug use and addiction.

Can a person overdose on marijuana?

An overdose occurs when a person uses enough of the drug to produce life-threatening symptoms or death. There are no reports of teens or adults dying from marijuana alone.

People have reported symptoms such as anxiety and paranoia, and in rare cases, an extreme psychotic reaction (which can include delusions and hallucinations) that can lead them to seek treatment in an emergency room.

Is marijuana addictive?

Marijuana use can lead to the development of a substance use disorder, a medical illness in which the person is unable to stop using even though it’s causing health and social problems in their life. Severe substance use disorders are also known as addiction.

Research suggests that between 9 and 30 percent of those who use marijuana may develop some degree of marijuana use disorder. People who begin using marijuana before age 18 are four to seven times more likely than adults to develop a marijuana use disorder.

Many people who use marijuana long term and are trying to quit report mild withdrawal symptoms that make quitting difficult. These include:

  • Grouchiness
  • Sleeplessness
  • Decreased appetite
  • Anxiety
  • Cravings

What treatments are available for marijuana use disorder?

No medications are currently available to treat marijuana use disorder, but behavioral support has been shown to be effective. Examples include therapy and motivational incentives.

Continuing research may lead to new medications that help ease withdrawal symptoms, block the effects of marijuana, and prevent relapse.

Source: NIDA. (2018, June 22). Marijuana. Retrieved from https://www.drugabuse.gov/publications/drugfacts/marijuana on 2019, March 29

* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.