What is the recommended treatment for allergies?

Treatment for Allergies

For allergic reactions, epinephrine is the first-line treatment for anaphylaxis, while antihistamines (H1 and H2) and corticosteroids are recommended for less severe allergic reactions or as adjunctive therapy. 1

Treatment Algorithm for Allergic Reactions

Anaphylaxis Management

• Epinephrine is the first-line treatment for anaphylaxis and should be administered immediately via intramuscular injection in the anterolateral thigh 1, 2
• For children weighing <25 kg: 0.15 mg epinephrine auto-injector; for those >25 kg through adults: 0.3 mg epinephrine auto-injector 1
• When using 1:1,000 epinephrine solution: 0.01 mg/kg with maximum dose of 0.5 mg 1
• Epinephrine doses may need to be repeated every 5-15 minutes if symptoms persist 1

Adjunctive Treatments for Anaphylaxis

• H1 antihistamines (diphenhydramine 1-2 mg/kg, maximum 50 mg IV or oral) - useful only for relieving itching and urticaria, not for treating respiratory symptoms or shock 1, 3
• H2 antihistamines (ranitidine 1-2 mg/kg, maximum 75-150 mg oral/IV) - may be used concurrently with H1 antihistamines 1, 3
• Corticosteroids (prednisone 1 mg/kg, maximum 60-80 mg oral) - primarily used to prevent recurrent or protracted anaphylaxis 1, 3
• Bronchodilators (albuterol) - for treatment of bronchospasm not responsive to epinephrine 1

Non-Anaphylactic Allergic Reactions Treatment

For Allergic Rhinitis

• Intranasal corticosteroids are the most effective medication for controlling symptoms of moderate to severe seasonal allergic rhinitis 1
• For patients who cannot tolerate intranasal corticosteroids, oral antihistamines (particularly second-generation) are recommended 1
• For moderate to severe seasonal allergic rhinitis in persons aged 12 years or older, the combination of an intranasal corticosteroid and an intranasal antihistamine may be recommended for initial treatment 1

For Mild Allergic Reactions

• Second-generation (non-sedating) H1 antihistamines like cetirizine, loratadine, or fexofenadine are preferred for daily management due to minimal sedative effects 4, 5
• Cetirizine has shown faster onset of action (within 1 hour) compared to loratadine (3 hours) in controlled studies 6
• In children ages 2-6 years with perennial allergic rhinitis, cetirizine has demonstrated greater efficacy than loratadine in relieving symptoms of rhinorrhea, sneezing, nasal obstruction, and nasal pruritus 7

Special Considerations

Allergen Immunotherapy

• Should be considered when positive test results for specific IgE antibodies correlate with suspected triggers and patient exposure 1
• Not recommended for patients with negative test results for specific IgE antibodies 1
• Particularly beneficial for patients whose symptoms are not well controlled by medications or avoidance measures 1

Follow-up Care After Allergic Reactions

• Education for patient and family on allergen avoidance and early recognition of symptoms 1
• For anaphylaxis: epinephrine auto-injector prescription (2 doses) with proper training 1
• Continuation of adjunctive treatment after discharge: H1 antihistamine (diphenhydramine every 6 hours for 2-3 days or non-sedating alternative), H2 antihistamine (ranitidine twice daily for 2-3 days), and corticosteroid (prednisone daily for 2-3 days) 1
• Follow-up appointment with primary healthcare professional, with consideration for referral to an allergist/immunologist 1

Important Cautions

• H1 antihistamines should never be used alone for anaphylaxis as they do not relieve stridor, shortness of breath, wheezing, GI symptoms, or shock 1, 3
• Asthma must be controlled at the time immunotherapy injections are administered 1
• First-generation H1 antihistamines cause sedation and cognitive impairment which may contribute to decreased awareness of anaphylaxis symptoms 1
• For patients on beta-blockers who may have reduced response to epinephrine, glucagon should be available as an additional treatment option 3