Anaphylaxis: intramuscular epinephrine may be absorbed faster than subcutaneous

Clinical bottom line (level 5)

  1. Healthy children with a history of anaphylaxis who received intramuscular epinephrine may have a faster time to maximum plasma concentration than children give subcutaneous epinephrine.
Simons et al: Journal of Allergy and Clinical Immunology 1998; 101: 33-37
Expires November 2004

The study

Single-blinded ?concealed randomised trial with intention-to-treat
Setting: allergy laboratory, Canada

17 patients (aged mean 8, ?% male) well children with a history of severe allergies and systemic anaphylaxis, who carried injectable epinephrine at all times

Excluded if
  • on other medication except inhaled or intranasal glucocorticoids
  • refused venipuncture
  • recent acute illness
  • requiring oral or injected medication within previous month
  • unable to discontinue beta-2-agonists for 24 hours before study or during the study
  • weight < 15 kg, > 40 kg
  • aged < 4 or > 12


    • Control Group: (n = 8, 8 analysed): intramuscular epinephrine 0.3 mg
    Experimental Group: (n = 9, 9 analysed): subcutaneous epinephrine 0.01 mg/kg to a maximum of 0.3 mg

    100% followed for 3 hours

    The evidence

    Outcome Control Group
    (SD)    		 Experimental Group
    (SD)    		 Mean Difference
    (95% CI)
    time to maximum epinephrine peak (minutes) 34
    (40)     		8
    (6)     		26
    (-3 to 55)

    Comments

    1. The study is too small to show any difference between the 2 groups.
    2. Children in the both groups received similar doses of epinephrine.
    3. Unclear whether these results apply to patients having an anaphylactic reaction.

    Citation

    1. Simons FE, Roberts JR, Gu X, et al: epinephrine absorption in children with a history of anaphylaxis. Journal of Allergy and Clinical Immunology 1998; 101: 33-37
    Search Terms: anaphyla* in Cochrane
    Contributor: Mike Bennett and Chris Ball, November 1999
    Reviewer: Chris Ball

    Clinical Question.
    Patient anaphylaxis
    Intervention or Exposure intramuscular epinephrine
    Comparison subcutaneous epinephrine
    Outcome absorption rates