Seven patients who applied corticosteroids topically under occlusive dressings acquired severe first-degree burns after exposure to sunlight. The response was unusual because normal skin, occluded but not treated with steroid creams, was more severely burned than the diseased areas. Skin-testing with artificial light showed the causative factor to be the modality (occlusion) rather than the medicine (steroids).
Cattano AN. Photosensitivity Following Treatment with Occlusive Dressings. Arch Dermatol. 1970;102(3):276-279. doi:10.1001/archderm.1970.04000090038006