Effect of menthone on the in vitro percutaneous absorption of tamoxifen and skin reversibility.

The effect of penetration enhancer (i.e., 1, 2, 3 and 5% menthone in combination with 50% ethanol (EtOH)) was investigated on the in vitro percutaneous absorption of tamoxifen, and post-recovery epidermal permeability after removal of the above enhancer. The flux of tamoxifen with menthone in combination with 50% EtOH was significantly greater (P<0.05) than the control (50% EtOH). The flux of tamoxifen increased with increasing concentrations of menthone. The post-recovery flux through enhancer exposed epidermis was significantly decreased (P<0.05) as compared to pre-recovery. However, post-recovery flux of tamoxifen through the enhancer-exposed epidermis did not completely recover to the baseline (i.e., post-recovery flux through phosphate buffered saline, pH 7.4 treated epidermis).