1. Home>
2. Specialties>
3. Dermatology>
4. Summary and Comment

Isotretinoin and Inflammatory Bowel Disease

Isotretinoin use was no more common in patients with IBD than in the general population.

Recently, questions about a link between isotretinoin treatment of acne vulgaris and development or exacerbation of inflammatory bowel disease (IBD) have been debated in the medical literature (and in the lay press). Several lawsuits have been filed against pharmaceutical companies and individual prescribers. Gastroenterologists with whom I have discussed this issue have given mixed answers as to whether they think the association is real or a coincidental observation. IBD is believed to result from a genetic susceptibility awakened by an environmental trigger; peak onset occurs in the third decade of life, with steady increases through the second decade.

Investigators at the University of Manitoba performed a province-wide case-control study to look for an IBD–isotretinoin association. They identified 2008 patients younger than 40 with physician and hospital claims coded for Crohn disease or ulcerative colitis, a method previously verified as highly sensitive and specific for identifying IBD. The investigators matched each case by age, sex, and geographic residence with 10 controls from the general population and then checked a pharmaceutical database for prescriptions to all study participants.

Twenty-five of the patients (1.2%) had been prescribed isotretinoin before receiving an IBD diagnosis, and 23 started isotretinoin after such diagnosis; the rate of isotretinoin use in patients who developed IBD did not differ from the rate of use among controls. The researchers found that isotretinoin use was rare in young IBD patients before IBD diagnosis and that isotretinoin use was neither more nor less prevalent in IBD patients than in the general population.

Comment: This well-designed and well-performed study used data that were easily obtained in a population covered by a single payer and whose drug use was recorded in a large database. The power of such a study to answer this and other questions is immense. This study did not address whether isotretinoin has an adverse effect on gastrointestinal mucosa, but the findings clearly demonstrate a lack of association between isotretinoin use and the development of IBD in the general population.

Unfortunately, some gastroenterologists, influenced by individual case observations, strongly believe in this association (as in the editorial by Shale and colleagues.), and some, perhaps, are willing to aid plaintiffs in complaints against pharmaceutical companies and prescribing physicians.

— Jeffrey P. Callen, MD

Published in Journal Watch Dermatology November 6, 2009

Citation(s):

Bernstein CN et al. Isotretinoin is not associated with inflammatory bowel disease: A population-based case–control study. Am J Gastroenterol 2009 Nov; 104:2774.

• Medline abstract (Free)

Shale M et al. Isotretinoin and intestinal inflammation: What gastroenterologists need to know. Gut 2009 Jun; 58:737.

• Original article (Subscription may be required)
• Medline abstract (Free)