Introduction: Food allergy is not a rare condition in post-transplant children. This report is the earliest transplant acquired food allergy case who developed anaphylaxis to cow’s milk under tacrolimus and steroid therapy.

Case Report: Nine month-old girl underwent living related liver transplantation for biliary atresia. Before transplantation she was breasfed and fed with minimal complementary nutrients. After transplantation she had been received total parenteral nutrition for a week. On seventh day posttransplantation, she was fed with cow’s milk based formula. Ten minutes after feeding, stridor and flushing developed under tacrolimus and steroid treatments. She was treated with intramuscular adrenaline. Scin prick test and spesific Ig E level suggested cow’s milk allergy. Cow’s milk and dairy products were eliminated from mother’s and patient’s diet and hydrolized Formula was recommended. At the age 28 month she developed tolerance to cow’s milk.

Conclusions: Medical staffs and families should be aware about development of food allergies in the early post-transplant period, despite the high dose immunsupressive therapy.