Medical marijuana is no stranger to controversy. New to the debate of what marijuana might treat is Crohn’s disease — an inflammatory bowel disease, which irritates and inflames the digestive tract, most often the small intestine. Recent reports suggest that marijuana, also called cannabis, could reduce or even eliminate Crohn’s symptoms, allowing people to cut back on medications, and more.
Cannabis for Crohn’s: What the Research Says
In 2011, Timna Naftali, MD, and a team of researchers at the Institute of Gastroenterology at Tel Aviv University in Israel published the first report on cannabis for Crohn’s disease. Their study included 30 people with Crohn’s who were treated with marijuana. 70 percent of the study’s participants improved significantly — needing less medication and less surgery than before using marijuana. The authors of the study, published in the Israel Medical Association Journal, concluded that cannabis for Crohn’s disease has a positive effect, but noted the need for further studies.
Which is exactly what Dr. Naftali and her team did — publishing the first placebo-controlled trial of cannabis for Crohn’s disease in the official journal of the American Gastroenterological Association, in October 2013.
The study included 21 people with Crohn’s disease with no response to the traditional medication used to treat Crohn’s. Eleven of the 21 participants were given marijuana cigarettes high in THC, an active ingredient in marijuana. The other 10 participants were given placebo cigarettes — marijuana cigarettes in which the THC had been removed.
After eight weeks, the researchers discovered:
- The average Crohn’s disease activity scores (CDAI) went down by about 177 points in the marijuana group, compared with about a 66-point drop in the placebo group.
- Complete remission of symptoms (a CDAI score of less than 150) was seen in 45 percent of the marijuana group and 10 percent of the placebo group.
- A significant response (a CDAI decrease of more than 100 points) was seen in 90 percent of the marijuana group, versus 40 percent of the placebo group.
- People in the marijuana group reported better sleep and better appetite, with no significant side effects.
Cannabis for Crohn’s: What the Experts Say
“The results are interesting, but they are based on tiny numbers,” said David E. Bernstein, MD, chief of the division of gastroenterology, hepatology, and nutrition at North Shore University Hospital-LIJ Medical Center in Great Neck, N.Y. “It would be dangerous to assume anything, or change anything, about cannabis for Crohn’s at this point.”
The study’s use of CDAI scores as a basis for benefits also concerns some. CDAI is a disease activity scoring system based on patients’ recordings in diaries they keep on disease responses. CDAI was developed in the 1970s, and some experts question how reliable a tool it is today.
“CDAI does take into account a patient’s general well-being, so euphoria from the cannabis would affect it,” Naftali said. “There are two possibilities: The anti-inflammatory effect of cannabinoids worked to ameliorate the disease, or the inflammation was the same but patients were in euphoria and felt better. However, some things hint towards a true anti-inflammatory effect. For example, the number of bowel movements was reduced.”
In addition to there being no hard evidence of reduced inflammation, she noted that most patients relapsed within two weeks of stopping the marijuana. Another caution is that smoking marijuana could damage the lungs. In future trials, Naftali said, the researchers would like to try an oral form of THC. “That could be better, but it needs to be investigated,” she said.
Cannabis for Crohn’s: Where to Go From Here?
“It is known that cannabinoids have anti-inflammatory properties in animal models,” Naftali said. “This study was the first to look at cannabis in a placebo-controlled trial in humans. The study was small, and disease activity was measured clinically but not in laboratory or endoscopic parameters, so further studies are needed.”
The Crohn’s & Colitis Foundation of America has also called for additional research. In a statement issued in March 2013, the foundation indicated that it supports further research but does not endorse smoking marijuana for Crohn’s disease. Despite some experimental evidence, it said there’s not enough direct scientific evidence to outweigh the potential side effects and dangers of medical marijuana.
“We need larger studies on cannabis and Crohn’s,” Dr. Bernstein said. “At this point, I would not change anything. Best bet is to stick to traditional treatments for Crohn’s disease.”
Naftali offered a slightly different take on the issue. “More studies are needed before we can be sure cannabis is indeed therapeutic,” she said, “so currently I would recommend it only to patients who did not respond to any other form of established treatment.”