Anaphylactic shock and severe acute urticaria induced by intramuscular injection of recombinant human interferon-α1b

A 36-year-old male patient with condyloma acuminatum received intramuscular injection of recombinant human interferon-α1b (RH-IFN-α1b) 50 μg once every two days. Six hours after the first injection, the patient developed high fiver and muscle pain. The symptoms disappeared about 8 hours later after going to bed and drinking hot water. He had no discomfort after the second to the fourth injection. About 5 minutes after the fifth injection, the patient developed amaurosis, irritability, chest tightness, palpitations, dyspnea, decreased blood pressure, increased pulse rate and respiratory rate, erythema and wheal in his trunk and face, and etc. He was diagnosed with anaphylactic shock and severe acute urticaria. He received the treatments of in horizontal position, oxygen inhalation, and anti-allergic medicine. Forty minutes later, the above-mentioned symptoms disappeared. Weakness, amaurosis, chest tightness, palpitations, and dyspnea recurred immediately at the 6th injection of RH-IFN-1b, and fecal incontinence and erythematous wheal appeared on the trunk 30 minutes later. RH-IFN-1b was stopped and the anti-allergic therapy was given. Three days later, the above-mentioned symptoms totally disappeared. Key words: Interferons; Anaphylaxis