What Are The 4 Types of Allergic Reactions? | Immediate hypersensitivity reaction
homeallergiescenterTopicGuideWhatAreThe4TypesofAllergicReactions?MedicalAuthor:JohnP.Cunha,DO,FACOEPReviewedon11/2/2020DefinitionWhatAreAllergicReactions?TypesWhatAreThe4TypesofAllergicReactions?SymptomsWhatAreSymptomsofAllergicReactions?CausesWhatCausesAllergicReactions?TreatmentWhatIstheTreatmentforAllergicReactions?GuideWhatAreThe4TypesofAllergicReactions?TopicGuideWhatAreAllergicReactions?Fourdifferenttypesofallergicreactionsareimmediate,cytotoxic,immune-complexmediatedanddelayedhypersensitivityreactions.Allergicreactionsoccurwhenthebody’simmunesystemhasareactiontoasubstanceitseesasharmful,calledanallergen. WhatAreThe4TypesofAllergicReactions?In1963,twoBritishimmunologists,RobertCoombsandPhilipGell,classifiedfourdifferenttypesofhypersensitivityreactions:Immediate(typeI)SymptomsappearafterafewsecondstominutesAnaphylacticreactions:themostsevereformofallergicreactionAnaphylaxisisamedicalemergencythatcanleadtosudden,life-threateningrespiratoryfailureSymptomsincludedifficultybreathing,swelling,lowbloodpressure,bluishskin,andshockIgEantibodiesareproducedbytheimmunesysteminresponsetoallergenssuchaspollen,animaldander,insectbites,dustmites,orcertainfoodsCytotoxic(typeII)SymptomsappearafterminutestohoursIgGandIgMantibodiesdamagecellsbyactivatingthecomplementsystemoftheimmunesystemsuchasin:AutoimmunehemolyticanemiaImmunethrombocytopenia AutoimmuneneutropeniaGoodpasturesyndromeGraves’diseaseMyastheniagravisImmunecomplex-mediated(typeIII)SymptomssetinafterseveralhoursIgMandIgGantibodiesreactwithallergenstoformimmunocomplexes(antigen-antibodycomplexes)suchasin: LupusSerumsickness ArthusreactionDelayedhypersensitivity(typeIV)SymptomssetinhourstodayslaterOfteninlong-terminfectiousdiseasessuchas: Tuberculosis FungalinfectionsWhatAreSymptomsofAllergicReactions?Symptomsofanallergicreactioninclude:Itchy,wateryeyesRunnynoseItchynoseSwellingSkinrednessSneezingRashesHives StomachcrampsVomitingDiarrheaBloatingPainCoughCall911andgettoahospital’semergencydepartmentifyouexperienceanysymp
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Allergic reactionType 1 hypersensitivityType 2 hypersensitivityType 3 hypersensitivityType 4 hypersensitivityimmediate hypersensitivity reaction中文immediate hypersensitivity中文Hypersensitivity reaction