What is the stepwise approach to managing a case of allergy?

Stepwise Approach to Managing Allergy Cases

The management of allergic disease follows a systematic three-pronged approach: establish a definitive diagnosis through clinical history correlated with objective testing, implement allergen avoidance strategies, and initiate pharmacotherapy with consideration of immunotherapy based on disease control and patient preference. 1

Step 1: Establish Definitive Diagnosis

Clinical History Assessment

• Document the specific symptom profile: nasal congestion, rhinorrhea, nasal pruritus, sneezing, ocular symptoms, respiratory symptoms, or systemic reactions 1
• Establish the temporal relationship between symptoms and suspected allergen exposure, including timing of symptom onset after ingestion/exposure 2
• Assess symptom severity, frequency, and impact on quality of life, including previous treatments attempted and their effectiveness 1
• Identify comorbid conditions such as asthma, which may affect treatment decisions and outcomes 2

Objective Testing

• Correlation of testing with clinical history is essential - positive test results alone (skin prick tests or serum-specific IgE) do not establish clinical allergy, only sensitization 2, 3
• Perform skin prick tests (SPTs) and/or serum-specific IgE tests to identify potential allergens 3, 4
• For food allergies where testing is equivocal, consider oral food challenge to confirm diagnosis after initial testing 3, 4
• No tests are available to predict severity of IgE-mediated reactions 2

Step 2: Implement Allergen Avoidance

Primary Management Strategy

• Complete avoidance of identified allergens is first-line treatment once specific allergens are confirmed 3, 1
• Implement specific avoidance measures based on confirmed allergen sensitivities rather than empiric elimination 1
• Provide education on environmental control measures relevant to identified allergens (house dust mite, pet dander, pollens) 1
• Train patients and caregivers on interpreting ingredient lists on food labels for food allergies 3

Nutritional Considerations for Food Allergy

• Provide nutritional counseling and regular growth monitoring, especially for children eliminating major food groups 3
• Ensure adequate nutritional intake through appropriate substitutions when implementing elimination diets 3

Step 3: Initiate Pharmacotherapy

For Allergic Rhinitis (Inhalant Allergies)

• Intranasal corticosteroids are the most effective first-line treatment for persistent moderate-to-severe allergic rhinitis, used alone or combined with intranasal antihistamines 1
• Prescribe second-generation oral antihistamines over first-generation agents to avoid sedation and anticholinergic effects 1
• For seasonal symptoms, initiate medication before the onset of the season for prophylaxis 2

For Food Allergy (Non-Anaphylactic Reactions)

• No medications are currently recommended to prevent IgE-mediated or non-IgE-mediated food-induced allergic reactions 3
• Antihistamines remain the mainstay for managing symptoms of non-severe allergic reactions 3
• For milder acute reactions (flushing, urticaria, isolated mild angioedema), treat with H1 and H2 antihistamine medications with ongoing observation 2

Step 4: Emergency Preparedness for Anaphylaxis

Recognition and Immediate Treatment

Intramuscular epinephrine is first-line therapy for anaphylaxis - all other drugs have delayed onset of action, and delays in epinephrine administration are associated with death and morbidity. 2

Concurrent Initial Steps (Do Not Delay for Sequential Approach)

• Eliminate additional allergen exposure 2
• Administer IM epinephrine immediately into the anterolateral aspect of the thigh 2, 5
• Call for help (911 in community setting, resuscitation team in hospital), though attempts to summon help should not delay epinephrine use 2

Dosing Specifics

• Adults and children ≥30 kg: 0.3 to 0.5 mg (0.3-0.5 mL) IM, up to maximum 0.5 mg per injection 5
• Children <30 kg: 0.01 mg/kg (0.01 mL/kg) IM, up to maximum 0.3 mg per injection 5
• Repeat every 5-10 minutes as necessary if suboptimal response or symptom progression 2, 5

Critical Pitfall to Avoid

The use of antihistamines is the most common reason for not using epinephrine and may place patients at significantly increased risk for progression toward life-threatening reactions. 2 The benefits of epinephrine far outweigh risks of unnecessary dosing. 2

Subsequent Steps After Epinephrine

• Place patient in recumbent position (if tolerated) with lower extremities elevated 2
• Provide supplemental oxygen 2
• Administer IV fluid (volume resuscitation) 2

Fatal Outcome Data

In a study of 13 fatal or near-fatal food-induced anaphylactic reactions in children, 6 of 7 children who survived received epinephrine within 30 minutes of ingesting the food, whereas only 2 of 6 children who died received epinephrine within the first hour. 2

Step 5: Post-Reaction Management (SAFE Mnemonic)

Seek Support

• Advise patients they are at risk for repeat episodes of anaphylaxis in the future 2
• At first sign of recurrence, self-administer epinephrine immediately, then call ambulance or go to nearest emergency facility 2

Allergen Identification and Avoidance

• Make efforts to identify the trigger through history and follow-up testing before discharge 2
• Emphasize importance of subsequent testing to verify the trigger for successful future avoidance 2

Follow-up with Specialty Care

• Follow-up with primary care within 1-2 weeks after anaphylaxis event 2
• Refer to allergist/immunologist for comprehensive evaluation, testing, diagnosis, and ongoing management 2, 3
• Implement regular follow-up testing depending on specific food allergen, patient age, and clinical history 3

Epinephrine for Emergencies

• Provide self-injectable epinephrine or prescription and educate on its use prior to discharge 2
• Advise patients and family members to routinely check expiration date of auto-injector 2
• Epinephrine should be available at all times to patients at risk 2

Step 6: Consider Immunotherapy

Indications for Immunotherapy

Offer allergen immunotherapy to patients with: 1

• Inadequate response to pharmacotherapy with or without environmental controls
• Requirement for high medication doses or multiple medications for disease control
• Adverse medication effects from standard therapy
• Desire to avoid long-term medication use
• Stinging insect hypersensitivity at risk for anaphylaxis

Critical Safety Requirement

Asthma must be controlled at the time of immunotherapy administration - this is a non-negotiable safety requirement. 1

Common Pitfalls to Avoid

• Failing to distinguish between sensitization and clinical allergy - positive IgE or skin tests require clinical correlation 2, 3
• Delaying epinephrine administration in favor of antihistamines during anaphylaxis - this is associated with fatalities 2
• Neglecting nutritional needs when implementing elimination diets 3
• Not providing emergency action plans for patients with confirmed food allergies 3
• Failing to prescribe epinephrine auto-injectors to at-risk patients 2