• The following information was developed by the Tacoma-Pierce County Health Department. 
    In 2012, Washington State voters approved Initiative 502 (I-502), which legalized recreational use of marijuana for adults 21 and older. The general consensus among health, safety, and substance abuse professionals is that marijuana use has health effects, use by youth is dangerous and addictive, use by pregnant and breastfeeding mothers is dangerous, smoke (of any kind) is harmful to a person’s health, and driving while under the influence of marijuana is not safe.

    It’s Legal, but Is It Healthy?

    Although now legal in Washington State for recreational use for those over 21, marijuana can cause health problems.

    Tacoma-Pierce County Health Department offers the following resources to help you make informed choices about marijuana:


    Marijuana, also known as pot, grass, reefer, weed, herb, Mary Jane, or MJ—is mixture of dried, shredded leaves, stems, seeds, and flowers of the cannabis plant. The chemical content and potency varies by plant part, species, variety, preparation, and location of cultivation. People smoke marijuana in hand-rolled cigarettes (joints), pipes, water pipes (bongs), or cigars (blunts) and consume it in food, such as in brownies or cookies.

    Health Effects of Marijuana

    Many marijuana users mistakenly believe that marijuana is not harmful because it is “natural” (unprocessed). While it may have some medicinal benefits, it also has negative health effects.

    Research has shown medicinal benefits of marijuana for specific medical conditions, such as, improving appetite following radiation and chemotherapy and treating chronic pain.

    Marijuana use is linked to negative physical, mental, emotional and behavioral health effects. These affect the user, who directly inhales the smoke, and bystanders, who inhale secondhand smoke.

    According to the American Lung Association and the National Institutes of Health, short-term health effects can include:

    • Impaired memory;
    • Delayed learning; and
    • Impaired driving.

    Long- term effects can include:

    • Lung impairment, such as chronic cough and bronchitis;
    • Immune system dysfunction;
    • An increased risk in vulnerable individuals, of developing certain types of mental illnesses, such as psychosis; and
    • Possible increase in cancer risk, such as lung and testicular cancers

    Marijuana and Youth
    Marijuana can impair brain development and functioning in youth. According to the California Society of Addiction Medicine:

    • The brain continues to undergo important development up until the age of 25;
    • Children and adolescents are at greater risk than adults of becoming dependent on marijuana, and dependence happens more quickly;
    • Children and adolescents are more significantly affected by marijuana;
    • Structural changes have been found in the brains of young marijuana users; and
    • Youth who use marijuana demonstrate subtle changes in emotions and reasoning, as a result of its use.

    Parents: What You Need to Know
    Tacoma-Pierce County Health Department has assembled several resources to help parents understand the health impacts of marijuana and to assist them in talking with their children about marijuana use.

    Marijuana: Facts Parents Need to Know, by the National Institutes of Health

    Marijuana: Facts for Teens, by the National Institutes of Health

    The Parent Toolkit, a Drug and Alcohol Resource for Parents

    What parents can say to their children, by Leslie R. Walker, MD, Chief of Adolescent Medicine, Seattle Children’s Hospital

    Learn about Marijuana: Science Based Information for the public, by University of Washington Alcohol and Drug Abuse Institute

    Department of Health’s resources for families and educators

    Marijuana and Washington’s Public Schools

    In a statement made by State Superintendent of Washington State Public Schools, Randy Dorn stated that “students need to be engaged and prepared for school. Marijuana doesn’t allow them to be either of those things. Marijuana dulls the brain. It can lead to paranoia, short-term memory loss and depression…It continues to be illegal on school property.”

    Recreational Marijuana in Washington State
    The Washington State Department of Health website includes additional information about marijuana.