What is the recommended dose and administration of adrenaline (epinephrine) for anaphylactic shock?

Adrenaline for Anaphylactic Shock

Administer epinephrine 0.3-0.5 mg intramuscularly (1:1000 concentration) into the lateral thigh immediately upon recognition of anaphylactic shock, repeating every 5-15 minutes as needed; if IV access is already established, consider IV epinephrine 0.05-0.1 mg (1:10,000 concentration) given slowly. 1, 2

Route Selection and Initial Dosing

Intramuscular administration is the preferred first-line approach because it provides rapid peak plasma concentrations, is easy to administer, and has a superior safety profile compared to IV administration 1, 2, 3. The injection must be given into the anterolateral aspect of the mid-thigh, never into the buttocks, digits, hands, or feet 3.

Intramuscular Dosing:

• Adults and children ≥30 kg: 0.3-0.5 mg (0.3-0.5 mL of 1:1000 concentration) 1, 3
• Children <30 kg: 0.01 mg/kg (maximum 0.3 mg) 3
• Repeat frequency: Every 5-15 minutes as needed based on clinical response 1, 2, 3

The FDA-approved labeling confirms these doses and emphasizes that the presence of sulfites in the formulation should not deter use in anaphylaxis 3.

Intravenous Administration

IV epinephrine should only be considered when IV access is already in place and is reserved for specific circumstances: profound hypotension unresponsive to IM epinephrine and IV fluids, or failure to respond to multiple IM doses 2.

IV Dosing Protocol:

• Bolus dose: 0.05-0.1 mg (5-10% of cardiac arrest dose) using 1:10,000 concentration 1, 2
• Administration: Give slowly over several minutes to minimize cardiovascular adverse effects 2
• Continuous infusion alternative: Add 1 mg (1 mL) of 1:1000 epinephrine to 250 mL D5W (concentration: 4 μg/mL) or to 100 mL saline (concentration: 10 μg/mL) 2

Critical distinction: The IV dose is dramatically different from the cardiac arrest dose (1 mg every 3-5 minutes), and using cardiac arrest dosing in anaphylactic shock without cardiac arrest can cause life-threatening arrhythmias and hypertension 2, 4.

Monitoring Requirements

Continuous hemodynamic monitoring is mandatory when administering IV epinephrine 1, 2. In settings without advanced monitoring capabilities, implement every-minute blood pressure measurements, continuous pulse monitoring, and ECG monitoring if available 2.

Potential Adverse Effects to Monitor:

• Tachyarrhythmias and ectopic beats 2
• Severe hypertension 2
• Potentially lethal arrhythmias, particularly in patients with underlying cardiac disease 3
• Extravasation causing severe skin injury (infiltrate with phentolamine if occurs) 4

Cardiac Arrest from Anaphylaxis

If anaphylaxis progresses to cardiac arrest, immediately switch to standard cardiac arrest protocols with epinephrine 1 mg IV/IO every 3-5 minutes using 1:10,000 concentration 1, 4. Standard BLS and ACLS measures take priority, and there is no proven benefit from antihistamines, inhaled beta-agonists, or IV corticosteroids during anaphylaxis-induced cardiac arrest 1.

Adjunctive Measures

Beyond epinephrine, aggressive fluid resuscitation is fundamental, as anaphylactic shock can cause up to 37% reduction in circulating blood volume due to vasodilation and increased capillary permeability 5.

Special Populations:

• Patients on beta-blockers: Consider glucagon 1-5 mg IV over 5 minutes followed by infusion, as beta-blockade may blunt epinephrine's effects 2
• Refractory hypotension: Consider alternative vasopressors such as dopamine 2-20 μg/kg/min 2

Critical Pitfalls to Avoid

• Delaying epinephrine administration while focusing on second-line treatments (antihistamines, steroids) is a major contributor to anaphylaxis fatalities 2, 6
• Using incorrect concentration: Never administer 1:1000 concentration intravenously—this is a potentially fatal error 2
• Administering IV epinephrine too rapidly increases risk of severe cardiovascular complications 2
• Injecting into inappropriate sites (buttocks, subcutaneous tissue) delays absorption and reduces efficacy 3
• Failing to repeat doses: Many patients require multiple doses, with symptom recurrence after 5-15 minutes being common 1

Airway Management Considerations

Given the potential for rapid development of oropharyngeal or laryngeal edema, immediate referral to a provider with expertise in advanced airway placement, including surgical airway management, is essential 1. When anaphylaxis produces obstructive airway edema, rapid advanced airway management becomes critical 5.