Phototherapy apparatus

The combination of UVA and certain photosensitive drugs is used to treat skin diseases, or black light therapy or photochemotherapy. Photosensitive drugs such as 8-methoxy-psoralen and trimethylpsoralen (TMP) can be taken orally. The drug molecules are activated by absorbing their energy under UVA irradiation, and covalentiously bind to two thymidines on the DNA chain in the cell to form thymine dimer. Through the photoaddition effect, the photosensitizer and thymine base form C4-cyclobutyl type photoadducts. Causing cell damage, injury or death