Background: Anaphylaxis associated with breast-feeding is a rare but potentially life-threatening event.
Case: This woman reported anaphylaxis with three previous pregnancies while breast-feeding. With her fourth pregnancy she was treated with corticosteroids and antihistamines after delivery. Despite treatment, she developed urticaria, facial edema, and throat tightening, less severe than prior episodes. Her symptoms resolved with epinephrine and antihistamine but recurred with subsequent breast-feeding. On postpartum day 4 she had no symptoms while breast-feeding.
Conclusion: Three cases of postpartum breast-feeding anaphylaxis have been reported. Although the pathophysiology is unclear, it may involve the decrease in progesterone and rise of prolactin causing mast cell degranulation. Avoidance of nonsteroidal antiinflammatories and prophylaxis with corticosteroids and antihistamines may offer the best protection.