Abstract: ：Objective To analyze rare allergic reactions caused by tramadol hydrochloride injection. Methods One case of allergic reactions (asthma) after tramadol hydrochloride injection in our Department of Anesthesiology in February 2019 was reported. Related literature was searched for retrospective analysis. Results A patient with chills after operation and anesthesia was twice treated with tramadol injection, resulting in asthma, faster heart rate and lower blood pressure. After emergency treatment, the patient returned to normal. Seven papers from databases were included and analyzed. Conclusion Tramadol should be used with caution. In case of such adverse reactions as shortness of breath or tachycardia, tramadol injection should be stopped immediately, while respiratory support should be provided and bronchodilators and antiallergic drugs should be given.

Key words: tramadol hydrochloride, asthma, adverse reactions, anaphylactic reaction