When is narrowband UVB phototherapy recommended for psoriasis?

Psoriasis is an inflammatory condition that can cause thickened, scaly plaques. Narrowband UVB treats exposed affected skin with carefully measured light and may be useful when creams are difficult to apply over broad areas. It may also be considered when a person prefers to avoid or cannot use certain medicines. The dermatologist will consider the type and location of psoriasis, skin tone, previous light reactions, medicines, and whether joints, nails or the scalp need separate treatment. Phototherapy is not a substitute for assessing joint pain.

Before starting, tell the clinic about light-sensitive medicines, previous skin cancers, unusual moles and any history of severe sun reactions. Attend the prescribed sessions and avoid adding sunbeds or deliberate tanning. Use eye protection and cover areas the team asks you to protect. Moisturise as directed, and report persistent redness, soreness, blistering or a new unusual mark. Keep appointments even as plaques improve so the dose and response can be reviewed safely.

Seek prompt advice if plaques become very painful, suddenly widespread, infected-looking or associated with fever. Urgent assessment is needed for a rapidly worsening generalised rash, skin shedding, severe weakness, or eye symptoms. Tell your clinician about new joint swelling or morning stiffness, since these symptoms may need a separate psoriasis assessment rather than a change to light treatment.

Ask which psoriasis areas are suitable, how response will be judged, what to do after a missed session, and whether your medicines alter light sensitivity. Ask how joint, nail or scalp symptoms will be treated if they do not respond to cabinet-based phototherapy.