What is the treatment for an allergic reaction to eating a peach?

Treatment for Allergic Reaction to Peach

Epinephrine is the first-line treatment for a severe allergic reaction to peach, administered intramuscularly at 0.01 mg/kg (maximum 0.5 mg) in the anterolateral thigh, which may be repeated every 5-15 minutes if symptoms persist. 1

Assessment and Classification

The severity of the allergic reaction determines the treatment approach:

Mild to Moderate Reaction (localized symptoms)

• Urticaria (hives)
• Mild angioedema
• Oral pruritus
• Mild gastrointestinal symptoms

Severe Reaction/Anaphylaxis (systemic involvement)

• Respiratory distress (wheezing, stridor)
• Hypotension
• Involvement of multiple organ systems
• Rapid progression of symptoms

Treatment Algorithm

1. Mild-Moderate Allergic Reaction

1. H1 Antihistamine:

   • Adults: Diphenhydramine 25-50 mg orally 2
   • Children: Diphenhydramine 1-2 mg/kg (maximum 50 mg) orally 2
   • Alternative: Second-generation antihistamines (cetirizine 5-10 mg) 1

2. Consider H2 Antihistamine (for better efficacy):

   • Adults: Ranitidine 75-150 mg orally 2
   • Children: Ranitidine 1-2 mg/kg orally 2

3. Observation for 4-6 hours to monitor for progression to anaphylaxis 1

2. Severe Reaction/Anaphylaxis

1. Epinephrine (FIRST LINE):

   • Adults and children ≥30 kg: 0.3-0.5 mg IM (0.3-0.5 mL of 1:1000 solution) 3
   • Children <30 kg: 0.01 mg/kg IM (maximum 0.3 mg) 3
   • Repeat every 5-15 minutes if symptoms persist 2

2. Positioning: Place patient in recumbent position with lower extremities elevated if tolerated 2

3. Adjunctive Treatments (only after epinephrine administration):

   • Oxygen: 8-10 L/min via face mask if respiratory distress present 2
   • IV Fluids: Normal saline in large volumes for hypotension 2
   • H1 Antihistamine: Diphenhydramine 1-2 mg/kg (maximum 50 mg) IV/IM/oral 2
   • H2 Antihistamine: Ranitidine 1-2 mg/kg IV/oral 2
   • Corticosteroids: Prednisone 1 mg/kg (maximum 60-80 mg) oral or methylprednisolone 1 mg/kg IV 2
   • Bronchodilator: Albuterol MDI 4-8 puffs or nebulized solution if bronchospasm present 2

4. Continuous Monitoring of vital signs until complete resolution of symptoms 1

Special Considerations

• Biphasic Reactions: May occur within 4-12 hours after initial symptoms resolve; observe patients for at least 4-6 hours after symptom resolution 4

• Refractory Anaphylaxis:

  • For patients on beta-blockers: Consider glucagon 1-5 mg IV followed by infusion of 5-15 μg/min 2
  • For persistent hypotension: Consider vasopressors 2

• Peach Allergy Specifics: The major allergen in peach is a lipid transfer protein, which can cause severe reactions even in patients without pollen allergies 5

Discharge Instructions

1. Epinephrine Auto-injector Prescription: Provide two doses and instructions on proper use 1

2. Continuation of Medications:

   • H1 antihistamine (diphenhydramine or non-sedating alternative) every 6 hours for 2-3 days
   • H2 antihistamine twice daily for 2-3 days
   • Corticosteroids daily for 2-3 days 2

3. Allergen Avoidance: Educate on strict avoidance of peaches and potentially cross-reactive fruits (apples, pears, cherries) 6

4. Follow-up: Refer to an allergist for comprehensive evaluation 4

Common Pitfalls to Avoid

• Delaying epinephrine administration in anaphylaxis can lead to fatal outcomes 1
• Using antihistamines or corticosteroids as substitutes for epinephrine in anaphylaxis 1
• Failing to recognize biphasic reactions which can occur hours after initial symptoms resolve 4
• Discharging patients too early without adequate observation period 1
• Rare hypersensitivity to antihistamines themselves can occur and complicate treatment 7

Remember that prompt recognition and appropriate treatment of allergic reactions to peach are essential to prevent progression to life-threatening anaphylaxis and ensure positive patient outcomes.