Summary Safety Review - Isotretinoin - Assessing the Potential Risk of Sacroiliitis

Isotretinoin-containing products

Sacroiliitis, inflammation of the sacroiliac joints (where the spine connects to the pelvis), usually resulting in pain

• Health Canada’s safety review found a possible link between isotretinoin and the risk of sacroiliitis.

• Health Canada is working with the manufacturers to update the product safety information in the Canadian product monograph (CPM) for isotretinoin-containing products to include the risk of sacroiliitis. Health Canada will also inform healthcare professionals about this update through a Health Product InfoWatch communication.

Health Canada reviewed the potential risk of sacroiliitis associated with the use of isotretinoin. The safety review was triggered by a labelling update by the European Medicines Agency.

• Isotretinoin is a prescription drug authorized for sale in Canada for the treatment of severe forms of acne in patients 12 years of age and older that should be used when the acne fails to respond to other treatments.

• Isotretinoin has been marketed in Canada since 1983. It is currently available as an oral capsule under the brand names Accutane Roche, Epuris and Absorica LD. Clarus, a generic version of isotretinoin, is also available in Canada.

• Approximately 361,000 isotretinoin prescriptions were dispensed by Canadian retail pharmacies in 2023.

• Health Canada reviewed the available information provided by manufacturers, as well as from searches of the Canada Vigilance database^a, international databases and the scientific literature.

• Health Canada reviewed 24 international cases of sacroiliitis in patients taking isotretinoin. Of those 24 cases, 23 were found to be possibly linked to the use of isotretinoin and 1 was unlikely to be linked. The average age was 20 years in cases where the age was provided. No deaths were reported among the 24 cases reviewed.

• Health Canada also reviewed 18 articles published in the scientific literature. While the studies supported a link between the risk of sacroiliitis and the use of isotretinoin, they did not identify a clear biological mechanism to explain how isotretinoin use could lead to sacroiliitis.

• In both the cases reviewed and the scientific literature, sacroiliitis improved after discontinuation of isotretinoin and appropriate treatment.

• Health Canada’s review of the available information found a possible link between isotretinoin and the risk of sacroiliitis.

• Health Canada is working with the manufacturers to update the CPM for isotretinoin-containing products to include the risk of sacroiliitis. Health Canada will also inform healthcare professionals about this update through a Health Product InfoWatch communication.

• Health Canada encourages consumers and healthcare professionals to report any side effects related to isotretinoin, and other health products, to the Canada Vigilance Program.

• Health Canada will continue to monitor safety information involving isotretinoin, as it does for all health products on the Canadian market, to identify and assess potential harms. Health Canada will take appropriate and timely action should new health risks be identified.

The analysis that contributed to this safety review included scientific and medical literature, Canadian and international information, and what is known about the use of isotretinoin both in Canada and internationally.

For additional information, contact the Marketed Health Products Directorate.