ABSTRACT
Angioedema is oedema in the dermis due to increased vascular permeability. A phototoxic rash looks like sunburn but occurs in a patient who has not been exposed to excessive sunlight. Acute sunburn presents as painful erythema with or without blisters, between a few hours and 2 days after sun exposure. Subacute eczema occurs without obvious vesicles and exudate. There will be erythematous patches and plaques where the border of the rash is ill defined merging imperceptibly into normal skin. Acute eczema on the face presents as tiny vesicles, weeping and crusting, and is usually due to an allergic contact dermatitis or atopic eczema. Herpes simplex is differentiated from impetigo by the history of recurrent episodes, prodromal pain and initial vesicles containing clear fluid, and in adults is the more likely diagnosis. The rash is usually symmetrical and uncomfortable and itchy rather than painful as in herpes zoster.
