University Health Service

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Key info for U-M students to know

It's illegal to:

  • possess or use cannabis if under age 21,
  • possess or use at any age on U-M property, and
  • use in public.

Learn more about laws and policies at U-M. Additionally:


Resources at U-M

If you're concerned about cannabis use, check out the resources below.


Cannabis is a rapidly evolving topic because:

  • Some states, including Michigan, have legalized the use of cannabis for medical and/or limited recreational purposes.
  • Cultivation of the plant is producing more potent and more specialized strains.
  • More products, and more ways to use products, are available now.
  • New research is better at identifying the effects of cannabis. This is due in large part to data collected from states that have legalized limited recreational use and because a ban on medical research has been lifted. We are better able to understand the comprehensive impact on individual well-being.

University Health Service helps students navigate this evolving issue and offers information and resources.


What students need to know about cannabis and their well-being

How common is cannabis use on campus?

According to the 2020 U-M National College Health Assessment, 72% of U-M students have NOT used cannabis in the past 3 months. That’s more than 34,500 students. 

Is it possible to have a bad reaction to cannabis?

Yes. Signs of a bad reaction may include extreme confusion, anxiety, paranoia, panic, fast heart rate, delusions or hallucinations, increased blood pressure, and severe nausea or vomiting. (Note the Medical Amnesty law protects people who call for help, if they invoke it at the time they call.) 

The effects of cannabis can be unpredictable because:

  • Cannabis products are not standardized or regulated by the Federal Drug Administration (FDA). The exceptions to this are cannabis products for specific medical use and can only be acquired with a prescription from a health care professional.
  • With edibles, it takes time to feel the full effects, and people may be inclined to consume more and then have a bad reaction. Learn more at Marijuana Edibles Fact Sheet from the County of Los Angeles Public Health.

How does cannabis affect the brain?

According to the Centers for Disease Control and Prevention (CDC), cannabis use directly affects the brain, specifically the parts of the brain responsible for memory, learning, attention, decision making, coordination, emotions, and reaction time.

  • Heavy users of cannabis can have short-term problems with attention, memory, and learning, which can affect relationships and mood.
  • Cannabis also affects brain development. When marijuana users begin using as teenagers, the drug may reduce attention, memory, and learning functions and affect how the brain builds connections between the areas necessary for these functions. 
  • Developing brains, like those in babies, children, and teenagers, are especially susceptible to the harmful effects of cannabis. Remember, the human brain is not fully developed until age 25. 

Does using cannabis solve sleep issues?

Some people use marijuana to self-treat sleep issues, including insomnia, anxiety, and pain.  Research is mixed on its effectiveness. It is understood that cannabis affects a person’s REM sleep and sleep cycles, which can impact the quality of sleep. It is best to consult with a healthcare provider for the best approach. Check out the UHS Sleep page for more information. 

How does cannabis affect mental health?

According to the CDC, cannabis use can affect mental health in the following ways:

  • Cannabis use, especially frequent (daily or near-daily) use and use in high doses, can cause disorientation, and sometimes unpleasant thoughts or feelings of anxiety and paranoia. 
  • Cannabis users are significantly more likely than non-users to develop temporary psychosis (not knowing what is real, hallucinations, and paranoia), and individuals with frequent use during adolescence may be more likely to develop chronic psychosis (most likely those individuals with a genetic vulnerability).
  • Cannabis use can exacerbate mental health issues like depression, anxiety, and suicidal ideation. 

How does cannabis affect the lungs?

  • The CDC recommends that you not use e-cigarette or vaping products that contain THC due to the risk of serious lung injury.
  • Smoked cannabis, in any form, can harm lung tissues and cause scarring and damage to small blood vessels. Smoke from cannabis contains many of the same toxins, irritants, and carcinogens as tobacco smoke. Smoking cannabis can also lead to a greater risk of bronchitis, cough, and phlegm production. 

How does cannabis affect drivers?

The National Institute of Drug Abuse (NIDA) discusses the impact of cannabis on drivers. It can slow drivers' reaction time and ability to make decisions, impair coordination, distort perception, and lead to memory loss and difficulty in problem-solving. Additionally, the effects of cannabis can affect a person’s decision-making and reaction times, sometimes for more than 24 hours, so plan ahead. 

Is it possible to become addicted to cannabis? 

Yes, according to the CDC, about 1 in 10 cannabis users will become addicted, called cannabis use disorder. For people who begin using before age 18, that number rises to 1 in 6.

How does cannabis affect a baby during pregnancy and breastfeeding?

  • Cannabis use by mothers during pregnancy may be linked to problems with attention, memory, problem-solving skills, and behavior problems in their children. 
  • Using cannabis while breastfeeding can allow harmful chemicals to pass from the mother to the infant through breast milk or secondhand smoke exposure.

What students need to know about cannabis-related laws:

  • The use of recreational or medicinal cannabis in any form, including edibles and extracts, is prohibited on university property by university policy and federal law. This is because federal law prohibiting cannabis preempts state laws that legalize the drug, and the university receives federal funding. 
  • Possession of cannabis on U-M property is a misdemeanor with the possible consequences of fines, arrest, and jail time. For anyone under 21, possession of cannabis in the city of Ann Arbor is a civil infraction with a fine that increases with each additional infraction.
  • In the city of Ann Arbor, it is illegal for anyone to use cannabis in public or drive under the influence of cannabis.

For more information about laws, please see Marijuana FAQs from the U-M Department of Public Safety and Security


Resources to discuss cannabis use and treatment


Are you in recovery or considering recovery from the use of cannabis, alcohol, or other drugs?

Learn more about the Collegiate Recovery Program, which provides holistic, tailored support to U-M students who are in recovery from alcohol or other drug problems.


More information

The CDC offers several excellent resources about the health and well-being effects of cannabis, including: