Triggers of Anaphylaxis in Mastocytosis Patients: Evidence of the Current Drug-Avoidance Recommendation

Opinion statement Mastocytosis is associated with a high risk of anaphylaxis, in part due to drug hypersensitivity reactions (DHR). Drugs associated with mast cell activation include nonsteroidal anti-inflammatory drugs (NSAIDs), drugs used in the perioperative setting, including general anesthetics, neuromuscular blocking agents (NMBAs) and opiates/opioids, radiocontrast media (RCM), vaccines, and antibiotics such as quinolones and vancomycin. To protect patients against DHR and anaphylaxis, general avoidance of potential drug triggers is common practice, which often deprives patients of important drugs at times of need and limits their options. We aimed to critically review current evidence on the indications to avoid drugs in children and adults with mastocytosis. Recent data shows that general avoidance of drugs with potential mast cell activation action is not indicated in all patients with mastocytosis, but guidelines are lacking. Drugs tolerated before and after the onset of mastocytosis should not be avoided and a personalized approach is recommended to address drugs inducing mast cell activation. Pre-medication (RCM, local and general anesthetics, vaccines), use of safer alternatives (opioids, NBMAs, NSAIDs in selected cases), and drug challenges (NSAIDs in most cases) are recommended to increase the safety of patients with mastocytosis when introduced to new drugs.