Monthly Lab Testing Not Necessary With Common Acne Medicine

Monthly laboratory testing may not be necessary for patients taking the standard doses of oral isotretinoin (13-cis retinoic acid; first marketed as Accutane) for the treatment of acne, according to a review and meta-analysis published online Dec. 2, 2015 in JAMA Dermatology. While the drug is known to adversely affect cholesterol and triglyceride levels, these changes usually occur early in the course of treatment and few effects are severe or high-risk. Thus, the authors say, less frequent laboratory monitoring may be cost saving and reduce patient discomfort and inconvenience.

The drug package insert recommends baseline fasting lipid and hepatic panels with repeated testing at weekly or biweekly intervals until “the response has been established,” but there are no specific suggestions for ongoing monitoring. In 2004 the American Academy of Dermatology published a consensus statement recommending periodic monitoring of serum triglyceride and cholesterol levels, as well as transaminase levels. But, dermatologists’ actual testing patterns are not known.

The current meta-analysis included 26 clinical trials (1,574 patients) of oral isotretinoin (lasting at least four weeks) in patients aged 9 to 35 years with acne vulgaris. Laboratory values for lipid levels, hepatic function, and complete blood cell count were evaluated. The study’s key findings were that isotretinoin is associated with a statistically significant change in the mean value of several laboratory tests (white blood cell count and hepatic and lipid panels), but that the mean changes across a patient group did not meet a priori criteria for high-risk or grade 2 abnormalities. Furthermore, the proportion of patients with laboratory abnormalities was low.

Most laboratory test abnormalities were detected early (typically between 6 and 8 weeks) during the treatment period and there were no substantial late adverse effects (up to 20 weeks) of isotretinoin therapy for the parameters measured—triglyceride and total cholesterol levels. (Later laboratory data were not available for other laboratory parameters.)

“A decrease in the frequency of laboratory monitoring for some patients could help to decrease health care spending and potential anxiety-provoking blood sampling,” write the authors led by Young H. Lee, M.D., from Sharp Rees-Stealy Medical Center in San Diego. “At our institution, we perform a lipid and hepatic panel at baseline and after two months of isotretinoin treatment, with more frequent monitoring dictated by baseline abnormalities and medical history.”

In an accompanying editorial lead author Kanade Shinkai, M.D., Ph.D., from University of California, San Francisco, suggests that despite the evidence and call for reduced monitoring, dermatologists may be limited in their willingness to accept new recommendations as a result of isotretinoin’s “notorious reputation” for drug-induced effects as noted by the “unusually high number of legal proceedings related to this particular drug.”