Non-Invasive Analysis of Penetration and Storage of Isoconazole Nitrate in the Stratum Corneum and Hair Follicles

The study investigated the penetration and storage of Isoconazole nitrate, an anti-fungal drug, in the stratum corneum and hair follicles using a differential tape stripping method over a 14-day application period and a 21-day follow-up. Conducted on 10 healthy volunteers, the study found that Isoconazole nitrate remained in concentrations above the minimal inhibition level in both the stratum corneum and hair follicles one week after application ended, and in some cases, even after 14 days. This indicated that hair follicles could serve as a long-term reservoir for the drug, providing a prolonged therapeutic effect. The study also confirmed that the differential stripping method was effective for analyzing the penetration and storage of topically applied substances without impairing the skin's barrier function.