− Before initiating therapy, o The patient should be screened for skin type o Patients should be aware of the long half-life of porfimer and that the compound gets activated by light. o Patients should avoid being exposed to light for 60-90 days post-exposure. o all patients should know that UV blocking is not effective in blocking visible light which activates porfimer. o Patients should be aware of potential risk factors (skin phototype and hepatic impairment). o Patients should be instructed to seek medical advice if signs/ symptoms suggestive of photosensitivity occur during or after therapy with porfimer.