A 63-year-old woman suddenly develops widespread urticaria, facial swelling and wheeze after taking an antibiotic. She is hypotensive and stridulous. What is the single most appropriate immediate treatment?AIntravenous chlorphenamineBIntramuscular adrenaline into the anterolateral thighCIntravenous hydrocortisoneDNebulised salbutamolESubcutaneous insulinCheck my answer