Journal of Environment and Health Science Journal of Environment and Health Science Journal of Environment and Health Science Journal of Environment and Health Science 2378-6841Ommega Online PublishersNew Jersey, USA8510.15436/2378-6841.15.007Research ArticleClarifying the Purported Association between Isotretinoin and Inflammatory Bowel DiseaseClarifying the Purported Association between Isotretinoin and Inflammatory Bowel DiseaseStevenS. CoughlinDepartment of Epidemiology Rollins School of Public Health Emory University Atlanta GAEditor* E-mail: stevecatlanta@aol.com
The authors have declared that no competing interests exist.
20152703201512JEHS-15-MRW-85/00719122014230320152015Creative Commons Attribution LicenseThis is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. nbsp emsp emsp Isotretinoin was approved by the Food and Drug Administration FDA in 1982 and revolutionized acne therapy Soon afterwards case reports appeared suggesting a link between inflammatory bowel disease and use of isotretinoin As reviewed in this article an increasing number of case-control and prospective cohort studies have been reported that examined associations between use of isotretinoin and inflammatory bowel disease Published epidemiologic studies of the use of isotretinoin and risk of Crohn rsquo s disease and ulcerative colitis vary according to whether the design was a case-control study or cohort study and by other important design differences The strengths and limitations of the studies such as their ability to control for important confounding variables e g the severity of acne and use of antibiotics also differ widely Results across epidemiologic studies have been inconsistent and most studies have not found a strong association or a dose-response relationship Based upon results from laboratory studies several biological mechanisms have been proposed to account for either a positive pathogenic or inverse protective association between isotretinoin and inflammatory bowel disease Although epidemiologic study findings are generally consistent with a correct temporal relationship Crohn rsquo s disease and ulcerative colitis often have an insidious onset with some symptoms occurring well before a clinical diagnosis of inflammatory bowel disease is made Taken overall results from epidemiologic case-control and cohort studies completed to date do not show a consistent association between isotretinoin use and risk of inflammatory bowel disease There is no clear evidence of a causal link 10