Methyl 5-aminolevulinate is the methyl ester of 5-aminolevulinic acid and functions as a prodrug. It is metabolized to protoporphyrin IX, a photosensitizer, used in photodynamic therapy for non-melanoma skin cancer, including basal cell carcinoma. Topical application, often as the hydrochloride salt, leads to protoporphyrin IX accumulation in treated skin lesions. Exposure to red light generates toxic singlet oxygen, damaging cell membranes and destroying tumor cells. It serves as an antineoplastic, photosensitizing, prodrug, and dermatologic agent, with functional similarity to 5-aminolevulinic acid.
