“I suspect there may be a relationship between dose and time before relapse, but not between dose and relapse incidence,” Dr. Leyden says.
As researchers sought to identify regimens that might maximize the duration of acne remission post-isotretinoin, studies were undertaken looking at the influence of varying the total cumulative dose as well as varying the total daily dose or adding other therapies during and post-isotretinoin.
“The general trend was to use higher and higher doses based on the idea that using more and more of the drug might make the improvement last longer,” Dr. Leyden says.
An important outcome of those studies, which is often overlooked, is that isotretinoin was highly effective even at a very low dose.
“A non-effective dose of isotretinoin for clearing very severe acne was not found – 0.1, 0.5, and 1.0 mg/kg/day were equally effective,” Dr. Leyden says.
1. Cunliffe WJ, van de Kerkhof PC, Caputo R, et al. Roaccutane treatment guidelines: results of an international survey. Dermatology. 1997;194(4):351-357.