How to manage an allergic reaction?

Management of Allergic Reaction to Otozambon

The immediate management of an allergic reaction to otozambon should focus on prompt administration of intramuscular epinephrine as first-line treatment, followed by supportive care based on symptom severity. 1

Initial Assessment and Classification

• Assess severity of the allergic reaction using clinical grading system: Grade I (mild, cutaneous symptoms), Grade II (moderate, multi-organ involvement), Grade III (severe, life-threatening), or Grade IV (cardiac arrest) 1
• Monitor vital signs immediately when symptoms are noted, but do not delay treatment for severe reactions 1
• Evaluate for signs of respiratory distress, hypotension, or mucosal swelling which indicate severe reaction 2

Immediate Management

First-Line Treatment

• Administer epinephrine intramuscularly into the anterolateral aspect of the thigh (through clothing if necessary) 3
  • Adults and children ≥30 kg: 0.3 to 0.5 mg (0.3-0.5 mL) of undiluted epinephrine 3
  • Children <30 kg: 0.01 mg/kg (0.01 mL/kg) of undiluted epinephrine, maximum 0.3 mg per injection 3
  • May repeat every 5-10 minutes as necessary based on clinical response 3

Fluid Management

• For hypotension or significant symptoms, administer rapid IV crystalloid fluids (20 mL/kg bolus, repeated as needed) 1
• Position patient with elevated lower extremities if hypotensive 1

Adjunctive Treatments (only after epinephrine administration)

• H1-antihistamines (e.g., diphenhydramine) for cutaneous symptoms 1
• H2-antihistamines (e.g., ranitidine) may be added but should not be used without H1-antihistamines 1
• Corticosteroids may be given for severe anaphylaxis to potentially prevent biphasic reactions, though evidence for this is limited 1, 2
• For bronchospasm, consider beta-2 agonists (e.g., albuterol) 1
• For refractory cases unresponsive to epinephrine, consider glucagon (especially in patients on beta-blockers) 1

Observation and Monitoring

• All patients should be observed in a monitored setting for a minimum of 6 hours from onset of reaction 1
• Severe reactions (Grade III and IV) typically require ICU admission 1
• Monitor for biphasic reactions (recurrence without re-exposure) for 4-12 hours depending on risk factors 2
• Repeat vital signs and physical examination every 15 minutes or more frequently during active anaphylaxis, then every 30-60 minutes after resolution until discharge 1

Post-Reaction Management

• Refer patient for specialized allergy investigation before any future procedures 1
• Collect serum tryptase levels (ideally within 1-2 hours of reaction onset) to confirm mast cell degranulation 1, 2
• Provide patient with detailed documentation of the reaction and suspected trigger 1
• Consider prescribing an epinephrine auto-injector for outpatient use if risk of recurrence exists 1

Prevention of Future Reactions

• Complete avoidance of the identified culprit agent in future exposures 1
• Ensure all healthcare personnel are informed about the patient's allergy to prevent accidental re-exposure 1
• For patients with recurring Grade I reactions, premedication with antihistamines may be beneficial 1
• Note that prophylaxis with H1/H2 antihistamines or corticosteroids does NOT reliably prevent or reduce the severity of true anaphylaxis 1

Special Considerations

• For patients with sensitive skin reactions to adhesives used during treatment, consider glycerin hydrogel dressings or non-adherent dressings with secondary securing methods 4
• Be aware that some reactions may be pseudo-allergic (non-IgE mediated) but still require similar acute management 5
• Distinguish between true allergic reactions and non-specific histamine release, which may affect future management 1

Remember that early recognition and prompt administration of epinephrine is the most critical intervention for managing allergic reactions, particularly anaphylaxis, and should never be delayed.