AGTR2 and anaphylaxis: However, in the European Anaphylaxis Registry, medications associated with an increased risk of severe anaphylaxis “risk cofactors” – such as ACEI, AT-2-antagonists (angiotensin II receptor type 2), ß-blockers, acetylcholine, and proton pump inhibitors – were significantly more frequently prescribed in older people (57%) than in younger adults (18%) [9].