Anesthesia in the patient with multiple drug allergies: are all allergies the same?

PURPOSE OF REVIEW During the preoperative evaluation, patients frequently indicate 'multiple drug allergies', most of which have not been validated. Potential allergic cross-reactivity between drugs and foods is frequently considered as a risk factor for perioperative hypersensitivity. The aim of this review is to facilitate the recognition of risk factors for perioperative anaphylaxis and help the management of patients with 'multiple drug allergies' during the perioperative period. RECENT FINDINGS Neuromuscular blocking agents (NMBAs) and antibiotics are the most common drugs triggering perioperative anaphylaxis. Quaternary ammonium ions have been suggested to be the allergenic determinant of NMBAs. Even though the 'pholcodine hypothesis' has been suggested to explain the occurrence of NMBA-induced allergy, this concept remains unclear. Although many practitioners believe that certain food allergies present an issue with the use of propofol, there is no role to contraindicate propofol in egg-allergic, soy-allergic or peanut-allergic patients. IgE-mediated hypersensitivity has been reported with seafood and iodinated drugs, IgE-mediated hypersensitivity has been reported with seafood and iodinated drugs, but there is no cross-reactivity between them. The allergenic determinants have been characterized for fish, shellfish and povidone iodine and remain unknown for contrast agents. SUMMARY There are many false assumptions regarding drug allergies. The main goal of this article is to review the potential cross-reactivity among specific families of drugs and foods in order to facilitate the anesthetic management of patients with 'multiple drug allergies'.