Acute allergic reaction: Difference between revisions

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==Management==
==Management==
#[[H1 agonist]]: [[diphenhydramine]] 50mg PO
#[[H1 agonist]]: [[Diphenhydramine]] 50mg IV/IM/PO
#[[H2 agonist]]: [[Ranitidine]]  
#[[H2 agonist]]: [[Famotidine]] 40mg OR [[ranitidine]] 150mg IV/IM/PO
#*Improves urticaria but not angioedema at 2 hours<ref>Lin, RY et al. Improved Outcomes in Patients With Acute  Allergic Syndromes Who Are Treated With  Combined H1 and H2 Antagonists. Annals of Emergency Medicine. 36:5 NOVEMBER 2000.</ref>
#*Improves urticaria but not angioedema at 2 hours<ref>Lin, RY et al. Improved Outcomes in Patients With Acute  Allergic Syndromes Who Are Treated With  Combined H1 and H2 Antagonists. Annals of Emergency Medicine. 36:5 NOVEMBER 2000.</ref>
*[[Corticosteroids]] are of questionable efficacy 
#Consider [[corticosteroid]]: [[Solumedrol]] 125mg IV/IM OR [[prednisone]] 60mg PO
*Rule out [[Anaphylaxis]]
#*Continue steroid burst if outpatient (40mg [[prednisone] PO x 5 days)
*Difficult to differentiate from [[Angioedema]]


==Disposition==
==Disposition==

Revision as of 06:47, 21 October 2015

Background

Clinical Features

Raised urticaria
  • Presentation can be delayed

Differential Diagnosis

Acute allergic reaction

Diagnosis

  • Clinical

Management

  1. H1 agonist: Diphenhydramine 50mg IV/IM/PO
  2. H2 agonist: Famotidine 40mg OR ranitidine 150mg IV/IM/PO
    • Improves urticaria but not angioedema at 2 hours[1]
  3. Consider corticosteroid: Solumedrol 125mg IV/IM OR prednisone 60mg PO
    • Continue steroid burst if outpatient (40mg [[prednisone] PO x 5 days)

Disposition

  • Consider brief observation in the ED for improvement of symptoms

See Also

References

  1. Lin, RY et al. Improved Outcomes in Patients With Acute Allergic Syndromes Who Are Treated With Combined H1 and H2 Antagonists. Annals of Emergency Medicine. 36:5 NOVEMBER 2000.