- Any use of light-activated drugs (photodynamic therapy) within 14 days prior to study enrollment (in US: Visudyne (verteporfin) - for age related macular degeneration; Aminolevulinic Acid- for actinic keratoses; Photofrin (porfimer sodium) - for esophageal cancer, non-small cell lung cancer; Levulan Kerastick (aminolevulinic acid hydrogen chloride) - for actinic keratosis; 5-aminolevulinic acid for non-melanoma skin cancer)