The stigma is fading, but learn the pros and cons before trying it.
Despite the hype and popularity of medical marijuana, you may not be sure if it’s something to consider. You’re right to be cautious; the use of marijuana to treat health problems is still being studied, and we don’t have all the answers about its risks and benefits.
We do know that medical marijuana use among older adults is increasing. “Older adults tend to use it for physical ailments. No. 1 is chronic pain. Insomnia is another big one, too. Older people have a hard time sleeping, and there aren’t a lot of other safe options,” says Dr. Peter Grinspoon, a primary care physician with Harvard-affiliated Massachusetts General Hospital.
What is medical marijuana?
The term “medical marijuana” refers to either the dried flowers of the unprocessed marijuana plant, which contains hundreds of chemicals; or two specific chemicals derived from marijuana that are known to have medicinal properties.
One of the two chemicals, tetrahydrocannabinol (THC), produces a high. The other, cannabidiol (CBD), does not produce any sort of high or cognitive impairment.
“The two chemicals separately, or in varying combinations, seem to decrease pain and to help with anxiety and insomnia. They are also thought to be helpful in reducing symptoms of many other conditions,” Dr. Grinspoon says. Those other conditions include arthritis, migraines, dystonia (a muscle disorder), multiple sclerosis, Parkinson’s disease, Crohn’s disease, fibromyalgia, and post-traumatic stress disorder. “CBD, in particular, is known to lessen inflammation and to be helpful in controlling epileptic seizures,” Dr. Grinspoon notes.
Forms of medical marijuana
Medical marijuana comes in many forms. You can obtain the dried marijuana flowers (buds), which can be smoked, vaporized and inhaled, baked into food, or used as a tea. The plants are grown in various strains, each of which has different ratios of tetrahydrocannabinol (THC) and cannabidiol (CBD).
You can also find products that contain THC, CBD, or both chemicals. The extracts are available in pills, concentrates (which are extremely potent), oils, sprays, sublingual drops, edibles (like gummies and other candies), patches, lotions, and suppositories.
Not without risks
While medical marijuana appears to have many potential health benefits, it also has risks.
THC and CBD can magnify or diminish the body levels of the medications you take. That could be dangerous with drugs that must be dosed carefully, with no room for error, such as the blood thinner warfarin (Coumadin).
Taking THC by itself may cause an elevated heart rate, impaired coordination, confusion, disorientation, dizziness, fatigue, hunger, nausea, red eyes, drowsiness, dry mouth, elevated blood pressure, or a sudden drop in blood pressure upon standing. “THC can also cause an anxiety attack if you take too high a dose, and it can affect short-term memory. If you have mild cognitive impairment, THC can make it worse and impair your judgment,” Dr. Grinspoon says.
The risks of THC dependence and addiction are debated; heavy users may experience withdrawal symptoms if they suddenly stop using it.
CBD doesn’t cause a “high” so you won’t be sedated while using it, but you will feel more relaxed. CBD side effects can include nausea, fatigue, irritability, low blood pressure, lightheadedness, drowsiness, diarrhea, or upset stomach. CBD is not considered addictive.
THC or CBD?
THC is a stronger drug. That might be helpful in certain cases. “Think of a veteran with severe pain from an injury who doesn’t want to be on opiates, or someone with severe pain from advanced cancer,” Dr. Grinspoon says.
But THC also has the disadvantage of psychoactive effects. For that reason, Dr. Grinspoon typically prescribes something high in CBD, with the lowest dose of THC possible. “You’ll get to the right dose,” he says, “but start low and go slow. Most of the side effects come from taking too much.”
If you’re interested
Medical marijuana is available in about three dozen states. Most require you to have a diagnosed “qualifying condition,” and all require a doctor’s referral so you can legally obtain the drug.
If you live in a state where recreational marijuana use is legal, you could simply go to a dispensary to buy it. But Dr. Grinspoon urges you to talk with your doctor before using any kind of marijuana for treatment purposes — not only to make sure it’s safe for your health but also to find out which chemical ratio you might need. “Educate yourself as much as possible before you enter a dispensary,” Dr. Grinspoon says, “so you’re not dependent on ‘budtenders’ [dispensary workers] who mean well but don’t have a medical background.”
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