While the clinicians play an essential role in the detection and assessment of the phototoxicity of novel drugs after their approval by health authorities, the critical task of collaborating physicists, chemists and molecular cell biologists is to unravel the molecular consequences of the propagation of the initial sunburn-like damage ending in skin cell death. In these instances the UVA-induced photooxidative stress plays a critical role. Using two representative examples, we review the modern findings resulting from our researches in this area from the eve of the 21^th century to date showing the need for complete examination of photochemical and photobiological properties to fully understand the damage to cell structures and functions that may ultimately lead to the most dramatic consequences such as long term cell photocarcinogenesis. In this short review we have chosen vemurafenib (Zelboraf™), recently used in the control of melanoma and voriconazole (Vfend™) prescribed for treatment of dreadfull fungal infections.