Should Most Oral Isotretinoin Patients Get Monthly Lab Testing?
The possible adverse effects of oral isotretinoin are well documented and routine laboratory testing of patients is recommended. The package insert recommends baseline fasting lipid and hepatic panels with repeated testing at weekly or biweekly intervals until “the response has been established.” Overall, the evidence to guide laboratory monitoring during isotretinoin therapy is limited by differences in tests ordered, testing frequency, and small sample sizes in published studies. A recent systematic review and meta-analysis sought to develop estimates of laboratory changes during isotretinoin therapy for acne. The authors wanted to clarify the data because they state that there are major differences between the guidelines in the package insert and multiple studies that suggest less frequent testing.
The results suggested that while 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), the mean changes across a patient group did not meet a priori criteria for high-risk and the proportion of patients with laboratory abnormalities was low. The authors conclude that the evidence from this study does not support monthly laboratory testing for use of standard doses of oral isotretinoin for the standard patient with acne. Less frequent testing for some patients could help to decrease health care spending and potential anxiety-provoking blood sampling.
The authors caution that despite these findings, clinical judgment should be used to determine monitoring frequency for each patient. Baseline laboratory findings and concomitant conditions, such as preexisting liver disease, concomitant use of hepatotoxic medications, or metabolic syndrome, may increase the risk of laboratory abnormalities and require more frequent monitoring.
Byline: Martha L. Sikes, MS, RPh, PA-C
Adapted from the original article.
[image by Dafne Cholet]