Marijuana has been used to treat the symptoms of gastrointestinal diseases for centuries. Few people know that until 1942, the drug had been widely prescribed for gastrointestinal disorders until its status as a legal medication was changed and marijuana was removed from the medical pharmacopeia.
Currently, scientists are beginning to realize the real medicinal value of the plant and investigate the effects of cannabis therapy on GI disorders.
Gastrointestinal disorders refer to a wide array of disorders that affect the gastrointestinal tract. There are more than forty different disorders varying in severity and lasting. We will explain the most common of them.
Irritable Bowel Syndrome (IBS). IBS is a disorder that affects the large intestine (colon). It usually causes abdominal pain, cramping, diarrhea, constipation, and bloating. IBS is a chronic disorder, meaning that it could last months and even years. Although the condition can be painful, it does not lead to other physical problems or damage the gastrointestinal tract. The causes of IBS are not clear, but experts think that genetic factors, food sensitivity, infection, and stress contribute to the disease.
Inflammatory Bowel Disease (IBD). IBD is a group of inflammatory disorders of the small intestine and colon. Crohn’s disease (affects any part of the gastrointestinal tract) and ulcerative colitis (affects the colon and rectum) are major forms of IBD. Although Crohn’s disease and ulcerative colitis are very different conditions, they both have similar symptoms: abdominal pain, rectal bleeding, vomiting, severe muscle spasms, weight loss, diarrhea, and anemia. IBD is caused by the interaction of genetic and environmental factors.
Anal and rectum disorders. These include hemorrhoids, anal fissures, perianal abscesses, fistula, and cancer. Inflammation of the rectum is known as proctitis. Anal pain and rectal bleeding are among the most common symptoms of the disorders.
Gastric diseases. Gastric diseases are often known as stomach diseases because they refer to illnesses affecting the stomach. Inflammation of the stomach is called gastritis, and inflammation of other parts of the gastrointestinal tract—gastroenteritis. When gastritis becomes chronic, it may lead to the development of more severe conditions, including pyloric stenosis, atrophic gastritis, and even gastric cancer. The most common symptoms are indigestion, vomiting, anemia, digestive problems, weight loss, and severe pain.
Treatment for GI disorders depends on the cause and severity of the condition and may include dietary changes, medication, or surgery. As most gastrointestinal disorders do not come without inflammation, the first step in the treatment is often the use of anti-inflammatory drugs. They include aminosalicylates and corticosteroids. Antacids are a common treatment for mild gastritis. Patients with IBS are usually prescribed fiber supplements (Metamucil and Citrucel), anti-diarrhea medications (Plevalite, Colestid, and Welchol), antispasmodic drugs (Levsin and Bentyl). In severe cases of IBS, antibiotic treatment can help. The drug treatment of anal and rectum disorders includes ointments containing anesthetics, steroids, nitroglycerin, and calcium channel blocking drugs. In some cases, it would be necessary to do surgery.
The drugs commonly prescribed to combat GI disorders have serious side effects, so doctors often recommend a few medications used in combination. For example, Prednisone, the most commonly prescribed drug to control Crohn’s disease, is a multi-purpose steroid that can cause psychosis, weak bones, glaucoma, high blood pressure, and stunted growth. The immunosuppressives also cause these side effects. The side effects associated with marijuana are relatively mild and are classified as “minor.”
Numerous studies have shown that marijuana, particularly its certain components, is effective in treating the symptoms of gastrointestinal disorders.
Pain in and around the organs called visceral pain is a GI syndrome caused by over-stretching, a destructive inflammatory process, or lack of blood flow. Pain affects the quality of life of patients who spend thousands of dollars on visits to doctors and expensive medication. However, painkillers often do not work or have severe side effects.
Marijuana helps get rid of the painful and often debilitating cramping that accompanies many gastrointestinal disorders. Cannabinoids relax the contractions of the smooth muscle of the intestine. A 2003 study conducted by Italian scientists revealed that THC reduced intestinal motility (spontaneous movement) and thus alleviated both abdominal pain and colonic spasms in IBS patients.
In 2015, researchers at the Temple University School of Medicine in Philadelphia reported that the CB1 and CB2 might play a role in the regulation of visceral sensation, intestinal inflammation, and cell proliferation in the gut.
Another study shows that cannabinoids may block gastrointestinal mechanisms that promote pain in IBS and related disorders. Moreover, all evidence suggests that the activation of cannabinoid receptors (CBRs) is beneficial for gut discomfort and pain—the upper GI tract is influenced by CB1R activation on central vagal pathways, whereas intestinal peristalsis can be modified by the cannabinoid activation in the absence of extrinsic input.
Cannabinoids have demonstrated the ability to block the gastrointestinal mechanism that promotes pain in IBS and related conditions. According to certain animal studies, cannabinoids also work well in controlling gastroesophageal reflux disease. It is a disorder for which a patient should use medications that have serious side effects.
Given the findings of the animal studies, scientists suggest that other cannabinoids (or their combinations) may also be effective in controlling pain and gut wall movement.
In the case of intestinal inflammation, the body increases the number of cannabinoid receptors in the area in an attempt to regulate the inflammation by processing more cannabinoids. CB2 receptors represent a pathophysiological mechanism for reducing intestinal inflammation.
Research on rodents shows that endogenous cannabinoids have crucial neuromodulatory function and are involved in controlling the operation of the gastrointestinal system. Particularly, synthetic cannabinoids control motility and inflammation by inhibiting fluid secretion.
One of the possible mechanisms of immune control by cannabinoids during inflammation is the regulation of cytokine production and disruption of the immune response. During chronic inflammation, cytokine can decrease tissue injury.
However, investigators reported both pro-inflammatory and anti-inflammatory effects of THC, proposing that different cell populations have varied thresholds of response to cannabinoids. Interestingly, while the anti-inflammatory cytokine called IL-10 decreased after the THC treatment, scientists observed an increase in the pro-inflammatory cytokine IL-8.
Finally, animal studies suggest that cannabis can be used as a possible medication for the treatment of intestinal hypermotility during secretion and motility disorders, as well as inflammatory bowel diseases and functional bowel diseases.
These symptoms occur in most of the gastrointestinal disorders, along with diarrhea, cramping, fever, bloating, sweating, chills, and weight loss. They come back again and again, varying in both duration and severity. Moreover, patients with severe nausea and retching often cannot tolerate the medications which, in their turn, cause side effects similar to the symptoms of IG disorders.
In 2010, researchers found that patients who experienced nausea had lower levels of the endocannabinoids called 2-AG and anandamide, increased levels of an endocannabinoid breakdown product, and fewer active CB1 receptors. Therefore, scientists suggested that a boost in cannabinoid or endocannabinoid receptor stimulation could decrease nausea.
According to the results of a 2005 study, patients with Crohn’s disease who used medical marijuana reported appetite improvements and beneficial effects for nausea, vomiting, weight gain, and depression.