CP94 is an iron chelator. It enhances protoporphyrin IX photobleaching and decreases in the viability of A431 squamous epithelial carcinoma cells when used at a concentration of 150 µM in combination with photodynamic therapy (PDT) mediated by the protoporphyrin IX precursors aminolevulinic acid (ALA), methyl aminolevulinate (MAL), or hexylaminolevulinate . CP94 (2 mg/ml in the drinking water) decreases hepatic total non-heme and ferritin-stored iron levels, as well as increases hepatic protoporphyrin levels, in mice. It also reduces ferrocene-induced increases in rat brain iron levels when administered at a dose of 100 mg/kg.