Marijuana is a drug that is made up of the leaves, flowers, and buds of the hemp plant Cannabis sativa. Medical marijuana is the use of this drug to help treat symptoms like pain, nausea, and lack of appetite. It may be used by people who have conditions like cancer, AIDS, or multiple sclerosis.
In Canada, it is against the law to possess, sell, give away, or grow marijuana without legal permission from Health Canada. People who have certain health problems can buy a limited amount of marijuana for their own use, and licensed people can grow and provide medical marijuana to those who need it.
Possession and use of medical marijuana must be authorized by a doctor as a medical treatment.
If you think you might want to try medical marijuana, talk to your doctor. You can also visit the Health Canada website at www.hc-sc.gc.ca/dhp-mps/marihuana/index-eng.php for more information.
The medical use of marijuana has been studied for decades. But experts still don't agree on how safe it is or how well it works.
Some medical experts don't recommend marijuana because:
Other medical experts do recommend marijuana because:
Be sure to let your doctor know if you are using medical marijuana. If you're pregnant, it is not safe to use alcohol or drugs, including marijuana.
Medical marijuana should only be used after the usual treatments with normal drugs have been tried. Marijuana interacts with many other medicines. It can be dangerous if taken with medicines that cause sleepiness or control mood, like sedatives, anxiety drugs, and antidepressants. Marijuana lowers blood sugar and blood pressure, so use caution if you take medicines for these conditions. It also increases the chance of bleeding if you are on blood thinners.
Marijuana is usually smoked. It can also be brewed into tea, vaporized, sprayed under the tongue, applied to the skin, or cooked in food.
You may be affected for hours after you use marijuana. How soon you feel the effects of marijuana and how long they last depends on many things, including:
Unwanted side effects may include:
Some people who regularly use marijuana become addicted. This means that they keep using marijuana even though it's having harmful effects on their lives.
The risk of addiction is higher in people who:
People who use marijuana often and then quit may have withdrawal symptoms. These include anxiety, trouble sleeping, and intense cravings for the drug.
Doctors can prescribe two legal alternatives. Both of these drugs contain a form of THC, the main chemical in marijuana.
Talk to your doctor if you think these medicines might help relieve your symptoms.
Synthetic marijuana is made of dried plant material that is treated with chemicals that produce effects like marijuana's effects. It is sold as incense under many names, such as K2 or Spice. The labels often claim that these products are "safe" or "natural." But in fact, the active chemicals are created in a lab. And they could be dangerous.
But young people often try these products because they are easy to buy and they may not be detected by drug tests.
People think that using these drugs will make them feel the same as when they use marijuana. But these drugs are different from marijuana. And the effects are hard to predict. That's because the type and strength of the chemicals used are often unknown. Some people have reported severe symptoms, such as:
Other Works Consulted
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ByHealthwise StaffPrimary Medical ReviewerE. Gregory Thompson, MD - Internal MedicineAdam Husney, MD - Family MedicineSpecialist Medical ReviewerMichael Seth Rabin, MD - Medical OncologyBrian D. O'Brien, MD - Internal Medicine
Current as ofNovember 21, 2017
Current as of: November 21, 2017
E. Gregory Thompson, MD - Internal Medicine
& Adam Husney, MD - Family Medicine & Michael Seth Rabin, MD - Medical Oncology & Brian D. O'Brien, MD - Internal Medicine
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