Pediatric Epinephrine Dose Calculator

Epinephrine Dosing for Anaphylaxis

Anaphylaxis is a severe, life-threatening allergic reaction requiring immediate epinephrine administration. Epinephrine works by reversing airway constriction, stabilizing blood pressure, and stopping the allergic cascade. Intramuscular injection into the thigh is the gold standard route because it provides rapid, reliable absorption with peak levels in 8-10 minutes.

The pediatric dose is 0.01 mg/kg up to a maximum of 0.5 mg, using 1:1000 epinephrine (1 mg/mL concentration). A 15kg child receives 0.15mg, which equals 0.15mL. A 60kg adolescent would calculate to 0.6mg but is capped at the 0.5mg maximum. Auto-injectors simplify this: EpiPen Jr delivers 0.15mg for children 15-30kg, while the standard EpiPen delivers 0.3mg for those over 30kg.

Timing is critical—epinephrine should be given at the first sign of serious allergic reaction: difficulty breathing, throat tightness, wheezing, significant swelling, or signs of shock (pale, weak, confused). Antihistamines like diphenhydramine are adjuncts that help with hives and itching but do not treat the life-threatening airway and cardiovascular components. Delaying epinephrine to give antihistamines first is a common and potentially fatal error. Epinephrine is always first-line treatment.

Cardiac Arrest Epinephrine Protocols

In pediatric cardiac arrest, epinephrine helps restore spontaneous circulation by increasing coronary perfusion pressure and improving myocardial contractility. The dosing, concentration, and route differ completely from anaphylaxis treatment, and confusion between protocols can be deadly.

For IV or intraosseous (IO) administration during cardiac arrest, the dose is 0.01 mg/kg using 1:10,000 concentration (0.1 mg/mL), with a maximum single dose of 1mg (same as adult dose). A 20kg child receives 0.2mg, which equals 2mL of 1:10,000 solution. This is given every 3-5 minutes during CPR until return of spontaneous circulation or resuscitation is terminated. The 1:10,000 concentration prevents accidental overdose during rapid administration in a chaotic resuscitation.

When IV/IO access is not available, epinephrine can be given via endotracheal tube (ET) at 0.1 mg/kg using 1:1000 concentration (1 mg/mL), maximum 2.5mg. This is 10 times the IV dose because absorption through the trachea is much less efficient. For a 20kg child, this equals 2mg or 2mL of 1:1000 epinephrine. However, IV/IO access is strongly preferred because ET absorption is unpredictable and may delay effective drug delivery.

Safety and Common Errors

Concentration confusion is the most dangerous error with epinephrine. Using 1:1000 for IV cardiac arrest dosing (instead of 1:10,000) delivers 10 times the intended dose and can cause severe hypertension, arrhythmias, and myocardial ischemia. Conversely, using 1:10,000 for anaphylaxis (instead of 1:1000) delivers only one-tenth the needed dose and may fail to reverse the reaction. Always verify concentration before drawing and administering epinephrine.

Route errors also occur: inadvertent intravenous injection of 1:1000 epinephrine intended for IM use can cause catastrophic outcomes. Auto-injectors are designed for IM use only and should never be used intravenously. Subcutaneous injection, once common for asthma and allergies, is now discouraged because absorption is slower and less reliable than IM administration.

Storage and expiration matter—epinephrine degrades when exposed to light and heat, turning brown or forming precipitates. Discolored or cloudy epinephrine should not be used. Auto-injectors have a shelf life of 12-18 months and must be replaced before expiration. In absolute emergencies, expired epinephrine is better than no epinephrine, but potency may be reduced. Families with children at risk of anaphylaxis should carry two auto-injectors in case a second dose is needed or the first device malfunctions.