Inflammatory Bowel Disease and Isotretinoin

Possible Association Between Isotretinoin and Inflammatory Bowel Disease

A recent article published in the American Journal of Gastroenterology has raised the possibility of an association between the use of Isotretinoin and the development of inflammatory bowel disease.

There are several causes of inflammatory bowel disease, most notable ulcerative colitis and Crohn’s disease, but the vast majority are non-specific.

This article is a retrospective analysis of reported adverse affects reamed from Medwatch reports and the FDA in the United States.

It is noteworthy in this paper that the authors state in their introduction that nearly 20 million prescriptions for Isotretinoin have been written since its approval in 1982 through to 2000. This study was conducted between the years of 1997 and 2002. Over the 5 year period that the study was conducted 85 cases of inflammatory bowel disease were reported as being possibly attributable to the use of Isotretinoin (Isotane).

The study did not conclude that there was a definite relationship between the use of this drug and inflammatory bowel disease, however 4 cases out of the 85, were reported as being in the highly probable range and have convincing data supporting an association between Isotretinoin use and the onset of inflammatory bowel disease in these patients. 68% of the 85 cases were reported as being a probable cause and the remainder were of possible cause.

Clearly 85 cases, over a 5 year period is a very small incidence given millons of prescriptions were written for Isotretinoin without reported association of inflammatory bowel disease.

Inflammatory bowel disease is however a serious disorder and can result in some severe symptoms and even hospitalisation.

The authors however note that it is possible that this represents a simple co-incidence and that inflammatory bowel disease tends to occur in younger people for which Isotane is commonly prescribed.

In the conclusion of the article the authors stipulate that Isotretinoin may unmask or trigger inflammatory bowel disease in pre-disposed patients.

Whist it is important that patients are aware of the possible connection between Isotretinoin and inflammatory bowel disease, I feel that this association is rare, if it does indeed occur. Patients who have a personal or family history of inflammatory bowel disease should be warned of the possible association and should patients develop any unusual bowel symptoms, such as altered habit and/or blood in the bowel motions, then this may be a marker of inflammatory bowel disease and the drug should be stopped.

The full text of the article can be found in the American Journal of Gastroenterology, 2006, pages 1569 through to 1573.

MARK H GRAY MBChB FRCPC FRCPA

Dermatologist / Dermatologic Surgeon / Dermatopathologist

23/8/06