Isotretinoin is not associated with inflammatory bowel disease: a population-based case-control study.

OBJECTIVES: There is anecdotal evidence that isotretinoin use is associated with development of colitis. We aimed at determining whether there is an association between isotretinoin use and development of inflammatory bowel disease (IBD).

METHODS: The population-based University of Manitoba IBD Epidemiology Database and a control group matched by age, sex, and geographical residence were linked to the provincial prescription drug registry, a registry that was initiated in 1995. The number of users and duration of isotretinoin use were identified in both IBD cases and controls.

RESULTS: We found that 1.2% of IBD cases used isotretinoin before IBD diagnosis, which was statistically similar to controls (1.1% users). This was also similar to the number of IBD patients who used isotretinoin after a diagnosis of IBD (1.1%). There was no difference between isotretinoin use before Crohn's disease compared with its use before ulcerative colitis.

CONCLUSIONS: Patients with IBD were no more likely to have used isotretinoin before diagnosis than were sex-, age-, and geography-matched controls. Although there may be anecdotes of isotretinoin causing acute colitis, our data suggest that isotretinoin is not likely to cause chronic IBD.