How long does photodynamic therapy take to work for actinic keratosis?

A photosensitising medicine is applied to the selected skin and activated with light. The reaction targets abnormal sun-damaged cells, so redness, burning, swelling, scaling, or crusting may appear first. These changes are part of a healing phase and can temporarily make the spot more noticeable. The treated skin then gradually becomes smoother as it repairs.

Response depends on how thick the lesion is, the body site, and whether the surrounding sun-damaged field was treated. A clinician may need to reassess a persistent rough patch rather than assuming it is still healing.

Keep the treated area protected from the light sources specified by your clinic for the advised period. Do not scratch, peel, or remove scale. Wash gently, apply the recommended bland product, and pause exfoliants or other irritating skincare until the surface has recovered. Keep follow-up so remaining roughness, tenderness, or a new lesion can be examined.

Seek advice if pain becomes difficult to control, redness spreads, swelling is severe, or drainage and fever suggest infection. Prompt assessment is also appropriate for a spot that repeatedly bleeds, develops a persistent ulcer, becomes thick or tender, or fails to settle after the expected healing period.

Ask when to expect peeling or crusting, when normal skincare and sun protection can restart, when the response will be checked, and whether a remaining rough area needs sampling or another treatment.