Abstract
The cofactors of anaphylaxis, seen in up to 30 % of cases, require screening for any of the aggravating circumstances that can cause the most severe clinical reactions. Drugs play a key role in this respect, with the following having all been incriminated: NSAlDs, beta-blockers, ACE inhibitors, angiotensin II receptor antagonists, proton-pump inhibitors and statins. Certain situations such as acute infections, exercise, alcohol consumption and patients' comorbidities (e.g., asthma, cardiovascular disease, mastocytosis) constitute further identified cofactors. The effect of certain hormones such as estrogens could play a role in the severity of anaphylaxis. The recently described elevation basal serum tryptase, hereditary alpha-tryptasemia has been reported to impact severe anaphylaxis notably in hymenoptera venom allergy.