U.S. federal law prohibits the use of marijuana. However, many states allow medical use to treat pain, nausea and other symptoms.By Mayo Clinic Staff
Medical marijuana is a term for derivatives of the Cannabis sativa plant that are used to ease symptoms caused by certain medical conditions. Medical marijuana is also known as medical cannabis.
Cannabis sativa contains many active compounds. The best known are delta-9 tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is the primary ingredient in marijuana that makes people "high."
Is medical marijuana legal in the U.S.?
U.S. federal law prohibits the use of whole plant Cannabis sativa or its derivatives for any purpose. In contrast, CBD derived from the hemp plant (less than 0.3% THC) is legal under federal law.
Many states allow THC to be used for medical reasons. Federal law regulating marijuana supersedes state laws. Because of this, people may be arrested and charged with possession even in states where marijuana use is legal.
When is medical marijuana appropriate?
Studies report that medical cannabis has possible benefit for several conditions. State laws vary in which conditions qualify people for treatment with medical marijuana. If you're considering marijuana for medical use, check your state's regulations.
Depending on the state, you may qualify for treatment with medical marijuana if you meet certain requirements and have a qualifying condition, such as:
- Alzheimer's disease
- Amyotrophic lateral sclerosis (ALS)
- Crohn's disease
- Epilepsy and seizures
- Multiple sclerosis and muscle spasms
- Severe and chronic pain
- Severe nausea or vomiting caused by cancer treatment
Is medical marijuana safe?
Further study is needed to answer this question, but possible side effects of medical marijuana may include:
- Increased heart rate
- Impaired concentration and memory
- Slower reaction times
- Negative drug-to-drug interactions
- Increased risk of heart attack and stroke
- Increased appetite
- Potential for addiction
- Hallucinations or mental illness
- Withdrawal symptoms
Some medical marijuana is formulated to provide symptom relief without the intoxicating, mood-altering effects associated with recreational use of marijuana.
Is medical marijuana available as a prescription medicine?
The U.S. Food and Drug Administration (FDA) has not approved the use of cannabis as a treatment for any medical condition. However, the FDA has approved the cannabinoids cannabidiol (Epidiolex) and dronabinol (Marinol, Syndros).
Cannabidiol can be used for certain forms of severe epilepsy. Dronabinol can be used for nausea and vomiting caused by cancer chemotherapy and for anorexia associated with weight loss in people with AIDS.
What you can expect
Medical marijuana comes in a variety of forms, including:
- Dried leaves
How and where you purchase medical marijuana varies by state. Once you have the product, you administer it yourself. How often you use it depends on its form and your symptoms.
Your symptom relief and side effects will vary based on which type you are using. The quickest effects occur with inhalation of the vaporized form. The slowest onset occurs with the pill form.
Certification and use at Mayo Clinic
Mayo Clinic health care providers may certify state residents with qualifying conditions in the Minnesota medical cannabis program. However, not all Mayo Clinic providers are registered for the certification process in Minnesota.
Minnesota residents with a supply of medical cannabis from a Cannabis Patient Center may continue use during their Mayo Clinic visit or hospital stay.
Arizona and Florida
Mayo Clinic campuses in Arizona and Florida do not certify people for medical marijuana or allow its use on campus or in the hospital.
- Arizona Department of Health Services: Medical marijuana
- Florida Health: Office of Medical Marijuana Use
- Minnesota Department of Health: Medical cannabis
- National Conference of State Legislatures: State medical marijuana laws
Dec. 04, 2021
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