According to the CDC:

Marijuana is the most commonly used illegal drug in the United States, with 22.2 million users. But the types of marijuana available today are more potent than before and come in many forms, including oils that can be vaped, and edibles, from brownies and candy to sodas. This leaves many with a lot of questions about marijuana use and its health effects.


Here are just a few of the health effects you may want to know:

  • Marijuana use directly affects the brain—specifically the parts of the brain responsible for memory, learning, and attention.
  • The compounds in marijuana can affect the circulatory system and may increase the risk of heart attacks and strokes.
  • Smoking marijuana can lead to a greater risk of bronchitis, cough, and phlegm production.
  • Marijuana users are significantly more likely than nonusers to develop chronic mental disorders, including schizophrenia. Schizophrenia is a type of mental illness where people might see or hear things that aren’t really there (hallucinations).
  • Eating foods or drinking beverages that contain marijuana have some different risks than smoking marijuana, including a greater risk of poisoning.
  • About 1 in 10 marijuana users will become addicted. For people who begin using before the age of 18, that number rises to 1 in 6.
  • Some research shows that using marijuana while you are pregnant can cause health problems in newborns—including low birth weight and developmental problems.
  • Marijuana use can slow your reaction time and ability to make decisions when driving.


Learn more about how marijuana use can impact your health by visiting CDC’s Marijuana and Public Health Web pages.

Marijuana Legalization and College: What You Need to Know

Recreational marijuana use has been legalized in several states and the District of Columbia, and other states have legalized medical marijuana. Are you considering attending a university or college in a marijuana-legal state? If so, here is what you need to know:


Adults in legalized states need to be 21 years of age or older to legally purchase and use recreational marijuana. Just as underage drinkers can be cited for alcohol use, persons under 21 caught with marijuana can be cited with a Minor in Possession court citation. Violators could also be referred to their school’s student conduct office—which will have and implement its own consequences above and beyond any of those associated with the court/legal system. 

Federal Guidelines Trump State Laws

Even if your college or university is in a legalized state, the institution is still required to abide by the federal Safe and Drug-Free Schools and Communities Act. This means the institution—whether public and private—must maintain policies prohibiting marijuana possession, use, or distribution by students, faculty and staff. Simply put, since marijuana is a Schedule 1 drug, it remains illegal at the federal level—even if the state has legalized use of marijuana. Schedule 1 drugs are those considered to have high potential for abuse and are not medically accepted for use in treatment. Colleges and universities receiving federal funds (e.g., federal financial aid, federal funding of research) must prohibit cannabis use on campus. As part of the school’s honor code or student code of conduct, some colleges and universities may even prohibit marijuana use off campus too.    

What If I Have a Prescription?

If you have a medical marijuana prescription, it is highly important that you proactively seek guidance from the student conduct and student affairs office of any university or college you are considering. Given that universities must abide by the Safe and Drug-Free Schools and Communities Act or risk losing federal funding, colleges and universities are not required to provide accommodations for students with a medical marijuana prescription. In other words, students with a medical marijuana prescription would need to store and use their prescribed marijuana at off-campus locations, which would restrict the student to off-campus residence options and preclude on-campus housing as a viable option.

Marijuana Use and Driving

Marijuana use negatively impacts many driving-related functions, such as judgment, motor coordination, and reaction time. Simply put, marijuana use negatively impairs driving ability—as THC concentrations in your body increase, your driving ability decreases. 

According to the Centers for Disease Control and Prevention (CDC):

While there is a nationally-recognized level of impairment for drunk driving (.08 g/mL blood alcohol concentration), standards for drugged driving vary from state to state. Since different types of marijuana, and edibles in particular, can vary greatly in strength and THC concentration, it would be difficult to know if you are over the limit in your state—and many states have a zero-tolerance law, meaning that any amount of THC in your system makes you over the limit. 

Both alcohol and marijuana—administered separately—negatively impact one’s reaction time and ability to maintain a car in a set position within a traffic lane. Combining alcohol and marijuana may produce effects dramatically greater than either drug on its own.  

Consequently, the absolute safest choice is to not have any marijuana, alcohol, or other drugs in your system when operating a motor vehicle. If you choose to use these substances, stay safe and use a ride-sharing service, call a cab, get a ride with a sober designated driver, or walk.    

Download this PDF for more information on driving while under the influence of marijuana.


Marijuana Anonymous (MA)
National Institute on Drug Abuse (NIDA)
Substance Abuse and Mental Health Services Administration (SAMHSA)