Acute IgE-mediated generalized urticaria-angioedema after topical application of povidone-iodine.

Povidone is a synthetic polymer mainly used as a dispersing or suspending agent for many pharmaceutical products. It is also used as a carrier for iodine. In many countries it is not mandatory its inclusion in drug labels so many adverse effects may be under diagnosed. Povidone-iodine used as a topical antiseptic solution may produce allergic contact dermatitis and irritation. Povidone, when systemically administered may deposit in tissues causing local lesions and pain. Three cases of immediate hypersensitivity to this agent have been reported. We present a patient who developed generalized urticaria and angioedema immediately after the first topical use of Betadine (povidone-iodine) on a right arm wound. The positive skin prick test to Betadine and povidone extract and the demonstration of serum specific IgE to povidone, confirmed an IgE-mediated hypersensitivity.