What is medical marijuana or medical cannabis?
Medical marijuana is the medical use of the Cannabis sativa or Cannabis
indica plant to relieve symptoms of, or treat diseases and conditions. The
Cannabis plant was used
medically for centuries around the world until the early 1900s. Medical
marijuana facts can be difficult to find because strong opinions exist, both
pros and cons. Medical uses and emerging research on off-label uses are summarized in
What are THC and CBD?
THC or tetrahydrocannabinolis the psychoactive compound in marijuana. It is
responsible for the "high" people feel. There are two man-made drugs called
dronabinol (Marinol) and nabilone (Cesamet) that are synthetic forms of THC.
They are FDA-approved to prevent nausea and vomiting in people
CBD or cannabidiol is another compound in marijuana that is not
psychoactive. CBD is thought to be responsible for the majority of the medical
Epidiolex is a CBD oil extract that is undergoing clinical trials for
THC:CBD: Nabiximols (Sativex) is a specific plant extract with an equal ratio
of THC:CBD. It is approved as a drug in the UK and elsewhere in Europe for the
treatment of multiple sclerosis, spasticity, neuropathic pain, overactive
bladder and other indications.
Medical marijuana products are available with a huge range of THC and CBD
concentrations. Expert opinion states that 10mg of THC should be considered "one
serving" and a person new to medical marijuana should inhale or consume no more
until they know their individual response.
Understanding Medical Marijuana: Laws, Uses, Safety
Medical Marijuana Types and Uses For Treatment
Medical marijuana or medical cannabis refers to any part of the marijuana plant that is used to treat health problems. Medical marijuana is not used to get "high." Some of the uses for medical marijuana are
- to control pain,
- to ease nausea,
- to treat loss of appetite,
- to treat some symptoms of multiple sclerosis, and...
What are the uses for medical marijuana?
Medical uses of marijuana include both studied and approved uses and
off-label uses. In a recent research survey, the most common reasons people use
medical marijuana are for
- muscle spasticity, and
- inflammatory bowel diseases such as Crohn's disease.
More research has been conducted on
the compound CBD. Medical CBD is anti-inflammatory, anticonvulsant, antioxidant,
neuroprotective, and anxiolytic, antipsychotic, and anti-emetic. The CBD
compound in medical marijuana appears to be neuroprotective in
disease, fetal hypoxia, and other neurodegenerative conditions
and movement disorders.
What are the health benefits of medical marijuana?
There are over 60 peer-reviewed research studies examining the benefits of
medical marijuana. Sixty-eight percent of these studies found benefit while 8%
found no benefit. Twenty-three percent of the studies were inconclusive or
neutral. Most research has been conducted on the compound CBD. The benefits of medical
be attributed to binding to the endocannabinoid system. This has many effects
- modulating the immune system,
- promoting neuroplasticity,
- emotional and
cognitive modulation including learning and motivation, appetite, vascular
function, and digestive function.
Are there any side effects of medical marijuana?
Medical marijuana side effects are minimal when used at low doses and include
At higher doses, side effects include
There are concerns about adverse effects of cannabis among adolescents
because the risks are greater to the immature brain and neurological system.
Concerns include increased risk of schizophrenia and loss of IQ.
There are public health concerns about the safety of driving under the
influence of medical marijuana. A JAMA study found lower rates of opioid
overdose deaths in states with legal medical marijuana.
Is medical marijuana legal?
At the time this article was written, 23 states have legalized medical marijuana with varying
restrictions. However, it is classified as a Schedule I substance by the Federal
Drug Administration (FDA), and thus is illegal at the Federal level. In most
states with legal medicinal marijuana, a prescription, authorization, or medical
recommendation is required, and a card or license is issued. This allows a person
to buy medical marijuana.
How do you get medical marijuana?
In states where medical marijuana is legal, shops, often called dispensaries,
sell marijuana products in a variety of forms. Medical marijuana is available in
edible forms (candies or cookies), oils and extracts, and as the plant which can
be smoked or otherwise inhaled. Dispensaries require a medical marijuana card
before they will sell products. How people can get a medical marijuana card
varies by state. It requires a prescription from a licensed health-care professional.
Is medical marijuana "addictive?"
Most research suggests a very low risk of addiction and very low toxicity of
medical marijuana when taken as recommended in low therapeutic doses. There is
concern about psychological dependence in heavy users and whether this
constitutes marijuana abuse. Some research has suggested CBD oil might be useful
in treatment for marijuana addiction or marijuana abuse.
What research is being done for medical marijuana?
There are numerous studies underway on medical marijuana, but research is
challenged by limited access given the FDA classification. A search of the
National Institutes of Health funded projects list in 2016 revealed 165 studies
related to cannabis and 327 studies related to the search term marijuana. The
majority of these studies are surveys into use patterns. Many are also basic
science studies investigating how the endocannabinoid system in the brain and
immune system works. Survey studies that anonymously assess users habits and
reported benefits may provide insight into the effects of real-world use
patterns. There are over 60 peer-reviewed research studies that have been
published about medicinal cannabis. Sixty-eight percent of these studies found
benefit while 8% found no benefit. Twenty-three percent of the studies were
inconclusive or neutral. The most promising areas of research appear to be
in the use of CBD for neuroprotection.
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Medically Reviewed on 8/31/2018
Medically reviewed by LaTonya B. Washington, MD; Board Certification in Internal Medicine and Pediatrics
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