Is it okay to give adrenaline (epinephrine) and Ringer's lactate to a patient with urticaria and itching after allergic food consumption, without anaphylaxis?

Management of Urticaria and Itching After Allergic Food Consumption

Epinephrine (adrenaline) should be administered intramuscularly for urticaria and itching after allergic food consumption, even in the absence of anaphylaxis, as it is safer to err on the side of treating early rather than waiting for more severe symptoms to develop. 1

Rationale for Epinephrine Use in Non-Anaphylactic Allergic Reactions

• Generalized acute urticaria, while not immediately life-threatening on its own, warrants epinephrine administration in the context of a known food allergen exposure, as it may progress to anaphylaxis 1
• The American Academy of Pediatrics recommends erring on the side of injecting epinephrine rather than waiting too long, especially when symptoms occur after exposure to a known allergen 1
• Prompt administration of epinephrine is key to preventing progression to more severe symptoms, as delayed administration has been implicated in contributing to fatalities 1, 2
• Individuals with food allergies, especially to peanuts, tree nuts, seafood, and milk, are at higher risk for severe reactions and should receive epinephrine promptly 1

Administration Protocol

• For adults and children ≥30 kg: 0.3-0.5 mg epinephrine intramuscularly into the anterolateral thigh 2, 3
• For children <30 kg: 0.01 mg/kg (up to 0.3 mg) epinephrine intramuscularly into the anterolateral thigh 2, 3
• Epinephrine doses may need to be repeated every 5-15 minutes if symptoms persist 1
• Ringer's lactate (or other IV fluids) should be administered in large volumes if the patient presents with orthostasis, hypotension, or incomplete response to IM epinephrine 1, 2

Adjunctive Treatments

• H1 antihistamine (diphenhydramine): 1-2 mg/kg per dose, maximum 50 mg IV or oral 1
• H2 antihistamine (ranitidine): can be added as adjunctive therapy 1
• Bronchodilator (albuterol): for bronchospasm if present 1, 2
• Supplemental oxygen therapy as needed 1, 2
• Place patient in recumbent position with lower extremities elevated if tolerated 1, 2

Post-Treatment Management

• All patients who receive epinephrine should be transferred to an emergency facility for observation 1
• Observation period of 4-6 hours is recommended, as biphasic reactions can occur 1
• Up to 25% of patients may experience a biphasic reaction (recurrence of symptoms several hours after initial reaction) 4

Special Considerations

• Serious adverse effects from epinephrine are generally not a concern for otherwise healthy individuals 1
• Common and anticipated pharmacologic effects include transient pallor, tremor, anxiety, and palpitations 1
• Caution is needed in patients with cardiovascular disease, those taking monoamine oxidase inhibitors or tricyclic antidepressants, and those with conditions like uncontrolled hyperthyroidism 1, 2

Common Pitfalls to Avoid

• Reluctance to use epinephrine due to fear of adverse effects or incorrect assessment of reaction severity 1
• Relying solely on antihistamines for treatment of allergic reactions after food exposure 1
• Failing to observe the patient after treatment, as biphasic reactions may occur 1, 4
• Administering epinephrine subcutaneously rather than intramuscularly (IM administration provides faster and more reliable absorption) 4

In conclusion, for patients with urticaria and itching after allergic food consumption, administering epinephrine IM and Ringer's lactate is appropriate and recommended, even without full anaphylaxis, as this approach prioritizes patient safety by preventing progression to more severe symptoms 1.