Photodynamic therapy (PDT) as a method used in the treatment of some types of cancer may also be used to treat some non-cancerous diseases of the skin or eye. PDT uses laser or other light sources, combined with a light sensitized drug (sometimes called a photosensitizing agent) to destroy cancer cells. Once the drug is accumulated in the tumour cells, if photons of ultraviolet and visible light (UV-VIS) are incident to them, the drug is activated and the cancer cells are destroyed. In the present work, we studied the photosensitizer properties of the cytostatic drug (methotrexate), used as photosensitizing agents, by its exposure to UV-VIS radiations. An experiment model for a possible clinical application was performed, also. Its effects ...