The US government classifies marijuana as a Schedule 1 controlled substance—a dangerous drug with no medical value. Yet the Institute of Medicine, an elite group of scientists and physicians, has concluded that the chemical compounds in marijuana do have therapeutic properties.
The wrangling between scientists and policy makers won’t stop anytime soon. Neither will the wrangling between the federal government and the states, 20 of which, along with the District of Columbia, allow the use of medical marijuana and two of which (Colorado and Washington) recently legalized marijuana for recreational use for people over age 21. But marijuana can be an effective medicine for some patients and can be very helpful in reducing pain. Caution: Always use medical marijuana under a doctor’s supervision.
Neuropathic pain. Researchers at the University of California, Davis, reported in The Journal of Pain that patients with neuropathy (nerve pain) who used cannabis (the word scientists prefer to the slang “marijuana”) were more likely to have significant relief than those taking a placebo. The chemical compounds in cannabis affect cell receptors in the brain, reducing pain and making it an alternative for patients who are unresponsive to standard drug therapies.
Neuropathy is common in diabetics, HIV patients and those with neuropathic disorders such as Guillain-Barré syndrome (in which the body’s immune system attacks the nerves) and Charcot-Marie-Tooth disease (hereditary motor and sensory neuropathy). The prescription medications that currently are used aren’t very effective. In my practice, about 90% of neuropathy patients who use cannabis have good results—often with fewer side effects than those who take drugs such as gabapentin (Neurontin).
Crohn’s disease. This is a potentially life-threatening inflammatory gastrointestinal (GI) disease that often causes severe abdominal pain, nausea and malnutrition, along with unpredictable bouts of diarrhea and/or constipation. Researchers at Tel Aviv University recently reported that 21 of 30 Crohn’s patients who used cannabis had less pain and were able to reduce their use of other medications. They also were less likely to require surgery.
The chemical compounds in cannabis reduce not only pain but also inflammation that causes ongoing tissue damage in the intestinal tract. Currently, some Crohn’s patients depend on narcotic medications for pain relief. Constipation is a common side effect of these drugs, which is dangerous for Crohn’s patients. Cannabis is safer because it doesn’t interfere with bowel movements.
Arthritis. The anti-inflammatory and pain-relieving substances in cannabis appear to make it a good choice for different forms of arthritis, including rheumatoid arthritis and osteoarthritis.
Weight loss from cancer treatment. Cancer patients who undergo chemotherapy and/or radiation treatments often suffer from severe weight loss and malnutrition. Cannabis stimulates appetite and can help patients get the calories they need to maintain a normal weight. Also, it’s easier for patients with nausea to inhale a medication than to take—and keep down—a pill.
In the past, cannabis often was recommended for nausea, even in the absence of weight loss. It was clearly more effective than the early generation antinausea medication dronabinol (Marinol), which is synthesized from cannabis-based compounds. However, newer drugs for nausea, such as ondansetron (Zofran), are probably more effective than cannabis.
HOW TO USE IT
I don’t recommend that my patients who use cannabis smoke it. Smoking can increase the risk for bronchitis or other respiratory problems. Better methods…
Vaporization. When patients use a vaporizer, the active compounds in cannabis “boil” and turn into vapor—the plant material doesn’t get hot enough to burn. This eliminates the harsh compounds in the smoke. It also causes less intoxication because the lower temperatures don’t activate tetrahydrocannabinol (THC), the compound that causes most of the “high” associated with smoking marijuana.
Sublingual tincture. With a prescription, you can buy this form of cannabis at some dispensaries. You also can make it at home by steeping about one ounce of cannabis flowers (available at dispensaries) in six ounces of glycerin for about a week. You put three or four drops under your tongue when you need a dose. It works almost as quickly as vaporized cannabis.
Juicing. You can put a small amount of cannabis in a blender, add your choice of liquids such as milk or juice, and drink it as a beverage. The intoxicating effects are reduced because the THC isn’t heated.
Some people eat cannabis by adding it to brownies or other prepared foods. Don’t do it. The intoxicating effects can be very strong. And because it can take an hour or longer to work, patients may think that they’re not getting enough. They consume even more—and wind up getting too much.
HOW MUCH TO TAKE?
Some cannabis dispensaries (and growers) use devices called gas chromatographs to measure the amounts of THC and other compounds in their products. This makes it easier to achieve batch-to-batch consistency. Typically, the cannabis sold by dispensaries has a THC concentration of about 15% to 20%.
Doctors who recommend cannabis usually rely on patient-titrated dosing. This simply means taking a small amount when you need a dose…waiting for about 20 to 30 minutes to see how you feel…and then increasing or decreasing subsequent doses, as needed. Effects typically last one to two hours.
WHAT AND WHERE TO BUY?
Different types of cannabis have markedly different effects. Cannabis that is rich in cannabidol (CBD) has fewer psychoactive effects than cannabis with a lot of THC. Patients who want to minimize the intoxicating effects can choose a strain with a higher percentage of CBD.
You can buy marijuana at dispensaries in the states where it is legal. Describe your symptoms to the clerk so that he/she can help you choose the right type of cannabis. If, for example, you have pain that mainly bothers you at night, you probably will want a cannabis that’s high in CBD—it will help you fall asleep. Patients with certain conditions where fatigue is a symptom and who need a “lift” might do better with a higher-THC product.
Recreational users of marijuana want to get high. For medical patients, this often is the main drawback.
I recommend to my patients that they “start low, go slow.” Take the lowest possible dose at first. Later, you can increase the dose if you need more relief. If you find that you’re getting intoxicated, use less.
Obviously, you shouldn’t drive, operate tools or machinery, or perform tasks that require a lot of concentration up to three hours after using cannabis, though residual effects have been reported up to 24 hours after using any medication that impairs mental functions.
Caution: If you have a serious psychiatric illness, such as bipolar disorder or schizophrenia, don’t use cannabis without the supervision of a psychiatrist. I don’t recommend cannabis for patients with a history of drug and/or alcohol abuse unless they’ve been referred by an addiction specialist.
Gregory T. Carter, MD, a physiatrist, clinical professor at the University of Washington, Seattle, and medical director of the Muscular Dystrophy Association Regional Neuromuscular Center in Olympia, Washington. His research interests include the use of cannabis and other treatments for amyotrophic lateral sclerosis (ALS). He is senior associate editor for Muscle & Nerve and coauthor of Medical Marijuana 101.Date: December 15, 2012 Publication: Bottom Line Personal