Late-onset allergic reaction to povidone-iodine resulting in vulvar edema and urinary retention.

BACKGROUND: Povidone-iodine, a surgical antiseptic, is associated with adverse side effects ranging from minor skin irritation to anaphylaxis, with symptoms occurring within minutes and up to 8 hours after contact. CASE: We report a case of a patient, with no history of allergy to povidone-iodine, who developed an allergic reaction 24 hours after intraoperative exposure to povidone-iodine, presenting with acute urinary retention secondary to extensive vulvar edema, which resolved after administration of antihistamines.
CONCLUSION: Allergic reactions to povidone-iodine can be late in onset and, in vaginal surgeries, may present with atypical symptoms such as acute urinary retention secondary to vulvar edema. Prompt diagnosis and effective treatment requires strong clinical suspicion in patients presenting postoperatively with a known history of exposure.