Phototherapy is the use of light in the treatment of skin diseases. It has been noted in ancient times that psoriasis often improves with exposure to the sun. Sunlight consists mainly of visible light, ultraviolet A and ultraviolet B (UVA and UVB) light. Phototherapy reproduces the action of sunlight in a scientific and controlled manner.
Several types of phototherapy are available. Narrow-band UVB (NBUVB), UVA/NBUVB (in combination) and PUVA (psoralen + UVA) are the common types used. Your doctor will advise you on the most appropriate phototherapy for your skin condition.
Phototherapy has been found to be effective in a range of skin conditions. It is used most widely in psoriasis, vitiligo and atopic dermatitis.