Anaphylaxis Treatment in Infants

Immediate Intervention

The American Academy of Pediatrics recommends immediate administration of intramuscular epinephrine 0.01 mg/kg (1:1000 solution) into the mid-outer thigh as soon as anaphylaxis is recognized, which is the only first-line treatment and must never be delayed or substituted with antihistamines or other medications 1, 2
Inject epinephrine 0.01 mg/kg of 1:1000 solution intramuscularly into the anterolateral thigh (vastus lateralis muscle) immediately upon recognition of anaphylaxis, as recommended by the American Academy of Pediatrics 3, 1
The intramuscular route in the lateral thigh achieves peak plasma concentrations in 8 ± 2 minutes, compared to 34 ± 14 minutes with subcutaneous injection, making it vastly superior for emergency treatment, according to the American Academy of Pediatrics 4

Position the infant supine with legs elevated (unless respiratory distress is present), as suggested by the American Academy of Pediatrics 6
Establish IV access, provide supplemental oxygen, and continuously monitor vital signs, as recommended by the American Academy of Pediatrics 2, 6

H1 antihistamines (diphenhydramine) are adjunctive only for cutaneous symptoms and should never be administered before or instead of epinephrine, according to the American Academy of Pediatrics 3, 2, 6
Inhaled albuterol may provide adjunctive therapy for wheezing in infants with preexisting asthma but does not replace epinephrine and does not treat upper airway edema or shock, as stated by the American Academy of Pediatrics 3, 5

All infants who receive epinephrine must be transported to an emergency facility for observation of 4-6 hours minimum or until stable and symptoms are regressing, as recommended by the American Academy of Pediatrics 1, 2, 6
Prescribe two epinephrine autoinjectors (0.15 mg for infants >7.5 kg) before discharge, according to the American Academy of Pediatrics 5, 1, 6

Delayed epinephrine administration is directly associated with anaphylaxis fatalities—never substitute antihistamines, corticosteroids, or bronchodilators as first-line treatment, as emphasized by the American Academy of Pediatrics 3, 2, 6
There are no absolute contraindications to epinephrine use in anaphylaxis—the benefits always outweigh the risks, according to the American Academy of Pediatrics 5, 6