UVB

Most individuals who have ultraviolet treatment for their psoriasis will be treated with UVB (narrowband) initially. This usually involves three exposures a week which are generally carried out in a Dermatology Department. To ensure the most appropriate starting dose of UVB, a patient’s back is exposed to a number of different UVB doses and the dose that produces a small amount of erythema after 24 hours is the dose that the first treatment is calculated upon. This is known as the minimal erythemal dose (MED). The speed at which these doses increase will depend to an extent on the individual’s skin type and their response to the therapy. During the administration of the UVB, individuals must wear glasses to protect their eyes and men should protect their genitalia with a jock strap. It is important that the same garment is used for each treatment, otherwise burning may result. If there are no lesions on the face, a full facial shield should be worn as well as goggles.