Anaphylaxis is a severe and potentially life-threatening reaction to a trigger such as an allergy. Important: Coronavirus (COVID-19). At the moment it can be ...SkiptomaincontentHomeHealthAtoZBacktoHealthAtoZOverview-AnaphylaxisContentsOverviewTreatmentPreventionAnaphylaxisisasevereandpotentiallylife-threateningreactiontoatriggersuchasanallergy.Important:Coronavirus(COVID-19)Atthemomentitcanbehardtoknowwhattodoifyou'reunwell.It'sstillimportanttogetmedicalhelpifyouneedit.Donotdelayifyoufeelveryunwellorthinkthere'ssomethingseriouslywrong.Call999.Symptoms ofanaphylaxisAnaphylaxisusuallydevelopssuddenly andgetsworseveryquickly.Thesymptomsinclude:feeling lightheadedorfaintbreathingdifficulties –suchasfast,shallowbreathingwheezingafastheartbeatclammyskinconfusion andanxietycollapsingorlosingconsciousnessTheremayalsobeotherallergysymptoms,includinganitchy,raisedrash(hives);feelingorbeingsick;swelling (angioedema) orstomachpain.WhattodoifsomeonehasanaphylaxisAnaphylaxisisamedicalemergency.Itcanbeveryseriousifnottreatedquickly.Ifsomeonehassymptomsofanaphylaxis,youshould:Useanadrenalineauto-injectorifthepersonhasone–butmakesureyouknowhowtouseitcorrectlyfirst.Call999foranambulanceimmediately(eveniftheystarttofeelbetter)–mentionthatyouthinkthepersonhasanaphylaxis.Removeanytriggerifpossible–forexample,carefullyremoveanystingerstuckintheskin.Liethepersondownflat–unlessthey'reunconscious,pregnantorhavingbreathingdifficulties.Giveanotherinjectionafter5to15minutesifthesymptomsdonotimproveandasecondauto-injectorisavailable.Ifyou'rehavingananaphylacticreaction,youcanfollowthesestepsyourselfifyoufeelableto.Readabout howtotreatanaphylaxisformoreadviceaboutusingauto-injectorsandcorrectpositioning.Triggers ofanaphylaxisAnaphylaxisistheresultoftheimmunesystem,thebody'snaturaldefencesystem,overreactingtoatrigger.This isoftensomethingyou'reallergicto,butnotalways.Commonanaphylaxistriggersinclude:foods–includingnuts,milk,fish,shellfish,eggsandsomefruitsmedicines–includingsome antibiotics andn