What is medical cannabis (marijuana)?
The term medical cannabis refers to using the whole, unprocessed marijuana plant or its basic extracts to treat symptoms of illness and other conditions. However, scientific study of the chemicals in marijuana, called cannabinoids, has led to two approved medications by countries that contain cannabinoid chemicals in pill form. Continued research may lead to more medications. Because the marijuana plant contains chemicals that may help treat a range of illnesses and symptoms, many people argue that it should be legal for medical purposes. In fact, a growing number of countries have legalized marijuana for medical use.
Countries require carefully conducted studies (clinical trials) in hundreds to thousands of human subjects to determine the benefits and risks of a possible medication. So far, researchers haven’t conducted enough large-scale clinical trials that show that the benefits of the cannabis plant (as opposed to its cannabinoid ingredients) outweigh its risks in patients it’s meant to treat.
Cannabinoids are chemicals related to delta-9-tetrahydrocannabinol (THC), marijuana’s main psychoactive ingredient. The marijuana plant contains more than 100 cannabinoids. Some of these cannabinoids are extremely powerful and have led to serious health effects when misused. The body also produces its own cannabinoid chemicals. They play a role in regulating pleasure, memory, thinking, concentration, body movement, awareness of time, appetite, pain, and the senses (taste, touch, smell, hearing, and sight).
Currently, the two main cannabinoids from the marijuana plant that are of medical interest are THC and CBD. THC can increase appetite and reduce nausea. THC may also decrease pain, inflammation (swelling and redness), and muscle control problems. Unlike THC, CBD is a cannabinoid that doesn’t make people “high.” These drugs aren’t popular for recreational use because they aren’t intoxicating. It may be useful in reducing pain and inflammation, controlling epileptic seizures, and possibly even treating mental illness and addictions. Many countries approved a CBD-based liquid medication called Epidiolex for the treatment of two forms of severe childhood epilepsy, Dravet syndrome and Lennox-Gastaut syndrome.
Researchers, are continuing to explore the possible uses of THC, CBD, and other cannabinoids for medical treatment.
For instance, recent animal studies have shown that marijuana extracts may help kill certain cancer cells and reduce the size of others. Evidence from one cell culture study with rodents suggests that purified extracts from whole-plant marijuana can slow the growth of cancer cells from one of the most serious types of brain tumors. Research in mice showed that treatment with purified extracts of THC and CBD, when used with radiation, increased the cancer-killing effects of the radiation.
Scientists are also conducting preclinical and clinical trials with marijuana and its extracts to treat symptoms of illness and other conditions, such as:
- diseases that affect the immune system, including:
- multiple sclerosis (MS), which causes gradual loss of muscle control
- substance use disorders
- mental disorders
Using Medical Marijuana During and After Pregnancy
Some women report using marijuana to treat severe nausea they have during pregnancy. But there’s no research that shows that this practice is safe, and doctors generally don’t recommend it.
Pregnant women shouldn’t use medical marijuana without first checking with their health care provider. Animal studies have shown that moderate amounts of THC given to pregnant or nursing women could have long-lasting effects on the child, including abnormal patterns of social interactions and learning issues.
Are People with Health- and Age-Related Problems More Vulnerable to Marijuana’s Risks?
State-approved medicinal use of marijuana is a fairly new practice. For that reason, marijuana’s effects on people who are weakened because of age or illness are still relatively unknown. Older people and those suffering from diseases such as cancer or AIDS could be more vulnerable to the drug’s harmful effects, but more research is needed.