What is the appropriate dosage and administration of adrenaline (epinephrine) 1:1000 dilution in emergency situations?

Adrenaline 1:1000 Dilution: Dosage and Administration

Adrenaline 1:1000 (1 mg/mL) is administered intramuscularly for anaphylaxis at 0.3-0.5 mg (0.3-0.5 mL) in adults and 0.01 mg/kg (0.01 mL/kg) up to 0.3 mg in children, injected into the anterolateral thigh every 5-10 minutes as needed. 1

Critical Safety Distinction

Never administer 1:1000 solution intravenously - this concentration is exclusively for intramuscular or subcutaneous use. 2 Intravenous administration requires the 1:10,000 dilution (0.1 mg/mL), as using the wrong concentration can result in potentially fatal 10-fold overdose. 2

Anaphylaxis Management (Primary Indication)

Adult Dosing

• 0.3-0.5 mg (0.3-0.5 mL) intramuscularly into the anterolateral aspect of the thigh 1
• Repeat every 5-10 minutes as necessary if symptoms persist 1
• Multiple doses may be required for severe hypotension or bronchospasm 3

Pediatric Dosing by Age

• >12 years: 500 μg IM (0.5 mL of 1:1000 solution); use 300 μg (0.3 mL) if child is small 3
• 6-12 years: 300 μg IM (0.3 mL of 1:1000 solution) 3
• Up to 6 years: 150 μg IM (0.15 mL of 1:1000 solution) 3
• Weight-based formula: 0.01 mg/kg (0.01 mL/kg), maximum 0.3 mg (0.3 mL) 1

Administration Technique

Injection Site

• Inject into the anterolateral aspect of the thigh - this provides more rapid plasma concentration increases compared to subcutaneous injection 2
• Never inject into buttocks, digits, hands, or feet - risk of tissue necrosis and inadequate absorption 1

Clinical Pearls

• IM administration in the thigh achieves therapeutic plasma levels (100-500 pg/mL) comparable to IV infusions 4
• Time to first dose is critical - early administration improves survival outcomes 5
• Seek medical care immediately if signs of infection develop at injection site, as rare serious soft tissue infections have been reported 1

Emerging Evidence for Cardiac Arrest

Recent animal studies and preliminary human data suggest potential benefit of IM adrenaline in cardiac arrest when IV/IO access is delayed:

• 5 mg IM dose in out-of-hospital cardiac arrest showed improved survival (11.0% vs 7.0%) and faster time to first dose (4.3 vs 7.8 minutes) compared to standard IV/IO administration 5
• Animal models demonstrate similar return of spontaneous circulation rates with IM versus IV epinephrine 6, 7
• This remains investigational and requires randomized controlled trials before routine clinical implementation 5

Contraindications and Warnings

• No absolute contraindications for anaphylaxis treatment 1
• Contains sulfites, but this should not deter use in life-threatening anaphylaxis 1
• Use with caution in patients with underlying heart disease - may aggravate angina or produce ventricular arrhythmias 1
• Higher risk populations include those with hyperthyroidism, Parkinson's disease, diabetes, and pheochromocytoma 1

Common Adverse Effects

Systemically administered epinephrine commonly causes: anxiety, apprehensiveness, restlessness, tremor, weakness, dizziness, sweating, palpitations, pallor, nausea, vomiting, headache, and respiratory difficulties. 1 Serious reactions include arrhythmias (including fatal ventricular fibrillation), rapid blood pressure rises producing cerebral hemorrhage, and angina. 1

Adjunctive Therapy for Anaphylaxis

After initial adrenaline administration:

• Chlorphenamine 10 mg IV (adult dose) 3
• Hydrocortisone 200 mg IV (adult dose) 3
• High-rate IV fluid resuscitation with saline 0.9% or lactated Ringer's solution 3
• Consider adrenaline infusion if multiple doses required (short half-life) 3