What is the treatment for an allergic reaction to licorice?

Treatment for Allergic Reaction to Licorice

The treatment for an allergic reaction to licorice follows standard allergic reaction protocols, with epinephrine as the first-line treatment for severe reactions (anaphylaxis), and antihistamines for mild reactions. 1

Assessment of Reaction Severity

Mild Reactions

• Few hives around mouth/face
• Mild itching
• Mild nausea/discomfort

Severe Reactions (Anaphylaxis)

• Diffuse hives
• Shortness of breath
• Respiratory symptoms
• Obstructive swelling of tongue and/or lips
• Circulatory symptoms

Treatment Protocol

For Mild Reactions

• H1 antihistamines (e.g., diphenhydramine 25-50 mg) for itching and urticaria 2, 1
• Avoid further licorice consumption
• Monitor for progression of symptoms

For Severe Reactions (Anaphylaxis)

1. Administer epinephrine immediately via intramuscular injection in the anterolateral thigh 2, 1

   • Adults and children ≥30 kg: 0.3-0.5 mg (0.3-0.5 mL)
   • Children <30 kg: 0.01 mg/kg, maximum 0.3 mg 3
   • May repeat every 5-15 minutes if symptoms persist

2. Call emergency services (911)

3. Additional adjunctive treatments:

   • Bronchodilators (albuterol) for bronchospasm
   • H1 and H2 antihistamines (diphenhydramine and ranitidine)
   • Corticosteroids to prevent biphasic reactions
   • IV fluids for hypotension
   • Supplemental oxygen as needed 2, 1

Post-Emergency Care

After stabilization, patients should receive:

• Anaphylaxis emergency action plan
• Epinephrine auto-injector prescription (2 doses)
• Plan for monitoring auto-injector expiration dates
• Follow-up appointment with healthcare provider and consideration for referral to an allergist 2

Prevention of Future Reactions

Complete Avoidance of Licorice

• Licorice (Glycyrrhiza uralensis) contains multiple bioactive compounds including glycyrrhizin, glycyrrhetinic acid, liquiritigenin, and isoliquiritigenin 2
• Patients should be educated to avoid:
  • Licorice candy and confections
  • Licorice tea and herbal remedies
  • Products that may contain licorice extract as flavoring 4

Allergy Testing

• Skin prick testing or specific serum IgE testing may be considered to confirm the allergy 2
• Testing should be performed by specialists in allergy or immunology

Special Considerations

Licorice Toxicity vs. Allergy

It's important to distinguish between an allergic reaction to licorice and licorice toxicity:

• Allergic reactions are immune-mediated and can occur after first exposure
• Licorice toxicity is dose-dependent and related to glycyrrhizic acid's mineralocorticoid effects, causing hypertension, edema, and hypokalemia 5, 4

Paradoxical Effects

Some studies suggest licorice components may have anti-allergic properties:

• Glycyrrhizic acid has shown anti-inflammatory effects in some research 6, 7
• However, this doesn't negate the potential for allergic reactions in sensitized individuals

Common Pitfalls to Avoid

• Delaying epinephrine administration in anaphylaxis (antihistamines should not be used in place of epinephrine for severe reactions) 2
• Discharging patients too early after anaphylaxis (observe for at least 4-6 hours due to risk of biphasic reactions) 1
• Failing to prescribe two doses of epinephrine auto-injector for patients with history of anaphylaxis 2
• Not providing adequate education about complete avoidance of licorice in all forms

By following these guidelines, healthcare providers can effectively manage allergic reactions to licorice while minimizing the risk of future reactions.