Transdermal Delivery of Photosensitizer by the Laser-Induced Stress Wave in Combination with Skin Heating

To investigate the effect of combining skin heating with a laser-induced stress wave (LISW) on the drug permeability of the skin, we attempted to deliver porfimer sodium (Photofrin II) into rat skin in vivo . We demonstrated that a mild heating (∼ 47°C) of the skin before applying the LISW enhanced the permeability of the drug into the skin. We suggest that the heating can increase the fluidity of the intercellular lipids and can cause swelling of the corneocytes, and therefore the LISW can easily form channels for drug transportation within the stratum corneum.