Intraoperative anaphylaxis and hypersensitivity reactions in the setting of anesthesia contribute significantly to the morbidity and mortality of surgeries and surgical procedures. Because multiple medications and products are given in a short period of time, identifying the specific cause can be difficult. Neuromuscular blocking agents, antibiotics, and latex are the most common causes of anesthesia-related reactions, though other medications or exposures could be involved. Careful review of anesthetic charts and allergy testing can help identify the underlying cause. The identification of the cause and subsequent prevention of reactions are critical to reduce overall mortality and morbidity related to anesthesia.