Cannabis drugs may benefit those with bowel disease

Aug 1 2005

UK scientists say they believe that patients with inflammatory bowel disease may benefit from cannabis-based drugs.

The research team at Bath University have found that people with the gut disorder had an abundant number of a type of cannabinoid receptors in their body.

This they believe is a part of the body's attempt to dampen down the inflammation and by giving a drug that binds to these receptors that attempt could be boosted.

People who have Crohn's disease or ulcerative colitis, known collectively as inflammatory bowel disease or IBD, have immune systems which go into overdrive, producing inflammation in different areas of the digestive tract; this causes symptoms such as pain and urgent diarrhoea.

It has been reported that in people with IBD who have been users of cannabis their symptoms get better when they use the drug.

In their study Dr Karen Wright and colleagues examined gut samples from healthy people and IBD patients and looked for the presence of two receptors known to react to natural cannabis-like compounds produced by the body.

It appeared that both the IBD patients and the healthy people had similar numbers of CB1 receptors in their gut, but the IBD patients had far greater numbers of CB2 receptors.

CB1 and CB2 receptors switch immune responses on or off, and CB1 receptors also help to promote wound healing in the lining of the gut.

Dr Wright says the study gives the first evidence that very selective cannabis-derived treatments may be useful as future therapeutic strategies in the treatment of Crohn's and ulcerative colitis.

This, she says, is because some extracts from cannabis, known as cannabinoids, closely resemble molecules that occur naturally in our body, and by developing treatments that target this system,the body can be helped to recover from some of the effects of the diseases

According to Dr Wright, although the psychoactive effects and the legal implications associated with herbal cannabis use make it unsuitable as a treatment, it might be possible to make a synthetic cannabis-like drug that has all of the therapeutic benefits and none of the other actions of cannabis.

Dr Derek Scott, a researcher at Aberdeen University, says the initial results look extremely promising and exciting, but further work is required.

Apparently cannabis-based medicines are already used for multiple sclerosis in some countries.

Dr John Zycheck, from the Peninsula Medical School in Plymouth, has been granted £2 million to study these drugs for MS, and says as they are already testing cannabinoids for a variety of different conditions, there is no reason why clinical studies could not be undertaken at a fairly early stage.

He says cannabinoids do have an effect on the gut in slowing gut transit as they have seen in MS patients, but more work was needed to check whether these drugs would reduce inflammation, and to work out a dose that was strong enough but not toxic.

Dr George Kunos from the U.S. National Institutes of Health says an alternative approach could involve testing compounds that amplify the action of the body's natural cannabinoids by blocking their normal destruction in the gut.

He says animal studies have suggested that compounds that block the enzyme fatty acid amidohydrolase do this.

Dr John Bennett, Chairman of Core, a national gut and liver disorders charity, also agrees that much more work is needed.

The findings appear in the journal Gastroenterology.