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Severe Allergic Reaction (Anaphylactic Shock) (cont.)


  • Epinephrine - Given in severe allergic reactions, epinephrine is extremely effective and fast-acting; it acts by constricting blood vessels, which increases blood pressure, and widening the airway. Epinephrine is given by injection into the muscle, through an IV line, or by injection under the skin.
  • H1-receptor blockers/antihistamines - Usually diphenhydramine (Benadryl); these drugs do not stop the reaction but relieve some of the symptoms. They may be given by IV, by injection in the muscle, or by mouth
  • Inhaled beta-agonists (albuterol) - Used to treat bronchospasm (spasms in the lung) and dilate the airways; inhaled
  • H2-receptor blockers - Usually ranitidine (Zantac); given by IV or by mouth
  • Corticosteroids (examples are prednisone, Solu-Medrol) - These drugs help decrease the severity and recurrence of symptoms; may be given orally, injected in muscle, or by IV line
  • If low blood pressure does not improve, additional medications, such as dopamine, may be given.
Medically Reviewed by a Doctor on 6/10/2014
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