Caffeine as a photoprotective agent for diminishing phototoxicity.

Skin whitening with Chinese herbal medicine has been used in ancient Asia. However, phototoxicity of the active ingredient limits the application. The modified comet assay was used in the current study to detect DNA crosslinking induced by phototoxicity. Result showed that caffeine at 5 µmol/L was able to reduce 5-methoxypsoralen-induced phototoxicity with ultraviolet C (UVC) exposure.