Marijuana can have a range of effects on the brain. It can affect mood, appetite, behavior, and pain sensation. Because of this, some have turned to marijuana to help manage certain medical issues. Not all uses of marijuana are fully supported by research but interest is growing.
Cannabinoids at Work
The effect of marijuana is caused by chemicals called cannabinoids. The most common are delta-9 tetrahydrocannabinol (THC) and cannabidiol (CBD), but there are hundreds more. How much of each type of chemical is in a plant will determine the effects it has. All the chemicals have a direct effect on the brain.
THC causes the "high" or euphoria associated with marijuana. Medical strands of marijuana may have low levels of THC. This means there is no or little feeling of "high" while still having medical benefits.
Medical marijuana may be available as:
Herbal—dried out buds or leaves that are smoked, vaporized, or eaten
Synthetic—created in a lab
Extracts—concentrated active ingredients can be used in pills or oils
Potential Uses for Medical Marijuana
Research needs to be done to support most medical use of marijuana. However, marijuana has been used to help manage the following:
Chronic or severe pain
Muscle spasms or stiffness
Complications of HIV and AIDS
Severe nausea and vomiting associated with chronic diseases or their treatments
Muscle wasting or severe weight loss associated with chronic diseases or their treatments
Manage seizures in children with certain types of epilepsy
Marijuana is often not the first choice for treatment. In many cases, it may be used only when other treatments have failed. It may also be an option if other treatment choices have unwanted side effects.
Side Effects of Marijuana Use
Marijuana, like any drug, can have side effects. Some can be serious. They can also vary between types of marijuana. Like any other drug, side effects will also depend on dose and how your body reacts to it.
Minor side effects may include:
Cognitive symptoms, such as confusion, and problems with memory and concentration
Slowed thinking and reaction time
Fatigue and drowsiness
Vertigo—a sensation of spinning when standing still
Serious side effects may include:
Severe or recurrent nausea and vomiting
Low achievement and lack of motivation
Dependency—increased tolerance and strong desire to use marijuana
Chronic bronchitis (and other tobacco-associated side effects)—if smoked
Irregular heart rhythm, which can lead to a heart attack or cardiac arrest
Development of mental illnesses, such as depression, anxiety disorders, bipolar disorder, schizophrenia, and psychosis
Suicidal thoughts or actions
Marijuana can also cause problem in pregnant women. It is linked with low birthweight, premature birth, and other complications for mother and baby. For this reason it is not recommended in women who are pregnant or planning to become pregnant.
Children and adolescents have rapidly growing brains. This makes them more vulnerable to the effects of any drug, even those given by a doctor. There is not enough research to know the exact effect of marijuana on younger brains. It is often only considered for extreme health concerns like uncontrolled seizures.
Where to Start
Talk with your medical team about your options. Marijuana can interfere with your treatment and other drugs. It is important to talk to your doctor before taking any new drugs. There may also be other, better understood treatments for your health issue.
Only get your medical marijuana from professional sources. This will make sure the marijuana is of high quality and proper dose. They will also have different strains to better meet your needs.
Know the Laws
Laws can vary. Check with the laws in your area for medical marijuana. Even if you have a prescription, there may still be some restrictions.
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This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.
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