The study examined the suggestion that specific ethanol-based skin antiseptics exhibit their efficacy on the resident skin flora of the forehead in only 2.5 minutes. Therefore the efficacy of two skin antiseptics based on 63% (w/w) propan-2-ol (iso-propanol) were examined and applied for 10 and 2 minutes on skin with a high density of sebaceous glands. Each experiment was performed in a reference-controlled cross-over design with at least 20 participants. Application of isopropanol (70%, v/v) for 10 minutes to the forehead served as the reference treatment. Pre-values and post-values (immediately after the application and after 30 min) were obtained by swabbing a marked area of 5 cm2 for about 10 s and investigated. The Wilcoxon matched-pairs signed-ranks test was used for a comparison of treatments. Skin antiseptics A and B were equally effective to the reference treatment when applied for 10 min as when applied for 2 min both immediately after application and after 30 min.