Light therapy or phototherapy means exposure to various types of light. This can be daylight or specific wavelengths of light provided by lasers, light-emitting diodes, fluorescent lamps, dichroic lamps or very bright, full-spectrum light, for a advised amount of time or at a specific time of day. Light therapy may be given to skin or to the eyes.
Absolute contraindications to light therapy include a condition that might render a patients eyes more vulnerable to phototoxicity, if the patient has a photosensitive skin condition, or is taking a photosensitizing herb (such as St. John's wort) or medication. Patients with porphyria should also avoid light therapy. If you using drugs like methotrxate, or chloroquine use light therapy with caution. Use light therapy under care of a specialist.