International Photodynamic Association (IPA)


International Photodynamic Association

International Photodynamic Association

The International Photodynamic Association (IPA) was founded in 1986 to support and endorse the scientific advancement and clinical development of photodynamic therapy (PDT), photoimmunotherapy (PIT), and photodiagnosis (PD). With members and associates from over 30 countries, the IPA represents a truly global community consisting of prominent international scientists, clinical and translational researchers, healthcare professionals and students across academic, hospital, government and private sector organizations. The IPA promotes the study of diagnosis and treatment using light-activated photosensitizers and disseminates scientific information to its members, the research community, and to the community at large. The IPA organizes a Biennial World Congress, providing members and non-members a unique opportunity to share and learn more about global developments and research in photodynamic therapy and photodiagnosis.




Photodynamic therapy (PDT) employs light-sensitive compounds known as photosenstizers (PSs) that when exposed selectively to light in conjunction with molecular oxygen become toxic to cells resulting in cell death. Many PSs exist today including: cationic dyes such as methylene blue, tetrapyrrole derivatives (phthalocyanines, chlorins, porphyrins), chlorophyll derivatives, and functionalized fullerenes.  

PDT, a minimally invasive treatment option, is used to treat many conditions including: acne, psoriasis, age related macular degeneration, and several cancers such as skin, lung, brain, bladder, bile-duct, esophageal, and head and neck cancers. PDT is also proven to eradicate pathogenic microorganisms Gram-positive and Gram-negative bacteria, yeasts and fungi.

Photodiagnosis (PD), also known as Photodynamic Diagnosis (PDD) is the use of light-sensitive compounds to indicate the presence of cancerous or diseased tissue. The same photosensitizers that are used for the treatment of cancer can also assist in its diagnosis. The emitted fluorescence from the activated photosensitizer can be used to differentiate cancerous from normal tissue guiding physicians during surgical resection. 

To learn more about the basics of photomedicine, the American Society for Photobiology (ASP) has a great free resource available on line.