Sun allergy on the feet: what to know

Polymorphic light eruption may affect the tops of the feet when footwear leaves strips of skin uncovered. The rash can follow a clear sandal or strap pattern and may itch, burn, swell, or form small blisters. Sweat, friction, shoe materials, insect bites, and fungal infections can also affect the feet, so the exact location and appearance are useful clues. The soles are less commonly exposed to direct ultraviolet light.

Cover the tops of the feet with socks or closed, breathable footwear and avoid direct sun while the rash settles. Cool the area, keep it clean and dry, and avoid scratching or tight straps. Stop a new sandal, cream, or adhesive if the rash follows its contact area. If episodes recur, take a photo before treatment and note the footwear and outdoor exposure. See [Sun Sensitivity](/symptoms/sun-sensitivity/) for related information.

Book an assessment if the rash affects the soles, spreads between the toes, cracks, oozes, or does not improve after sun avoidance. Prompt care is needed for increasing pain, warmth, swelling, pus, fever, or difficulty walking. Emergency help is appropriate for facial swelling, breathing difficulty, or widespread blistering. These signs may point to infection or another reaction rather than a simple sun-triggered rash.

Ask whether the shape matches ultraviolet exposure or contact with footwear, whether any medicine can increase light sensitivity, and how to protect the feet without trapping moisture. For repeated episodes, discuss whether [Narrowband UVB Phototherapy](/treatments/medical-dermatology/narrowband-uvb-phototherapy/) is relevant and whether [Topical Corticosteroids](/treatments/medical-dermatology/topical-corticosteroids/) is suitable for the affected skin.