Hematoporphyrin Derivative

**Semantic type:** Pharmacologic Substance

**Definition:** A complex mixture of monomeric and aggregated porphyrins with photosensitizing activity. Upon systemic administration, hematoporphyrin derivatives accumulate in tumor cells and, once activated by red laser light (630 nm), in the presence of oxygen, produce singlet oxygen and other reactive oxygen radicals, resulting in local radical-mediated tumor cell death.