Phototherapy is the use of ultraviolet light, which is found in sunlight, for the treatment of skin disease. Although natural sunlight is sometimes used for certain diseases, artificially produced ultraviolet light is generally used as it is easily controlled, is available and is convenient and less time consuming for patients. The phototherapy equipment available in the department has capability of producing UVB and UVA. UVB is short wavelength UV that is often used in the hospital to treat psoriasis. UVA is longer wavelength UV used with the drug psoralen in the treatment referred to as PUVA and is generally used in an outpatient setting. In addition, narrow band UVB is now available.

Phototherapy is most frequently used to manage psoriasis. It is also helpful in the treatment of a multitude of other skin problems, including: cutaneous T-cell lymphoma, vitiligo, lichen planus, granuloma annulare, pityriasis rosea, acne, generalized itching from various causes, diseases of the hands and feet, atopic and other types of eczema.