What is the recommended dosage of prednisone (corticosteroid) for a patient with an allergy, considering factors such as age, weight, and medical history?

Prednisone Dosing for Allergic Reactions

For allergic reactions, prednisone should be dosed at 1 mg/kg daily (maximum 60-80 mg) for 2-3 days without tapering. 1, 2

Dosing by Clinical Scenario

Anaphylaxis (Post-Emergency Treatment)

• Prednisone 1 mg/kg daily (maximum 60-80 mg) for 2-3 days as part of discharge management after anaphylaxis 1, 2
• This is purely adjunctive therapy—corticosteroids provide no acute benefit and should never replace or delay epinephrine administration 1, 2
• The rationale is to potentially prevent biphasic reactions (which occur in up to 20% of cases within 3 days), though evidence supporting this practice is limited 1, 2
• No tapering is required for these short 2-3 day courses 1, 2

Acute Urticaria (Outpatient Management)

• Prednisone 20 mg orally every 12 hours for 4 days (total 40 mg/day) added to antihistamines significantly improves symptom resolution 3
• For antihistamine-resistant chronic urticaria, prednisone 25 mg/day for 3 days induces remission in approximately 47% of patients, with effects appreciable within 24 hours 4
• A second short course may be attempted if the first course produces temporary improvement but relapse occurs, achieving remission in an additional 9% of patients 4

Asthma Exacerbations

• Outpatient burst: 40-60 mg daily in single or 2 divided doses for 5-10 days in adults 5
• Pediatric dosing: 1-2 mg/kg/day (maximum 60 mg/day) for 3-10 days 5
• No advantage exists for higher doses or intravenous administration over oral therapy when gastrointestinal absorption is intact 5
• For courses ≤10 days, tapering is unnecessary, especially if patients are concurrently taking inhaled corticosteroids 5

Pediatric Considerations

• Standard dose: 1 mg/kg daily (maximum 60 mg) for allergic reactions 2
• Duration: 2-3 days without tapering 2
• For asthma exacerbations specifically, the dose range is 1-2 mg/kg/day divided in 2 doses (maximum 60 mg/day) 5
• In anaphylaxis management, consider corticosteroids particularly for children with asthma history, severe reactions requiring multiple epinephrine doses, or prolonged symptoms 1

Critical Clinical Algorithm

For Mild Allergic Reactions (isolated urticaria, flushing):

• Start with H1 and H2 antihistamines alone 2
• Add prednisone 20-25 mg daily for 3-4 days if symptoms persist despite antihistamines 4, 3
• Close observation is mandatory to detect progression to anaphylaxis 2

For Anaphylaxis:

1. Immediate IM epinephrine 0.3-0.5 mg (adults) or 0.01 mg/kg (children)—this is the ONLY first-line treatment 1
2. Repeat epinephrine every 5-15 minutes as needed for persistent symptoms 1
3. After stabilization and 4-6 hour observation period, discharge with:
   • Prednisone 1 mg/kg daily × 2-3 days 1, 2
   • Two epinephrine auto-injectors with training 1
   • H1 and H2 antihistamines 1
   • Written anaphylaxis action plan 1

For Hospitalized Patients with Severe Reactions:

• Methylprednisolone 1-2 mg/kg IV divided every 6 hours (typically 40 mg every 6 hours for a 70 kg adult) 1
• Alternative: Hydrocortisone 100 mg IV 1

Administration Timing and Practical Considerations

• Administer in the morning (before 9 AM) when possible, as this aligns with peak adrenal cortex activity and minimizes HPA axis suppression 6
• Take with food or milk to reduce gastric irritation 6
• For multiple daily doses, space evenly throughout the day 6
• Consider antacids between meals when using large doses to prevent peptic ulcers 6

Common Pitfalls to Avoid

Never use corticosteroids as monotherapy for acute allergic reactions—they have a 4-6 hour onset of action and provide no acute benefit 2. The most dangerous error is substituting antihistamines or steroids for epinephrine in anaphylaxis, which significantly increases mortality risk 2.

Do not extend duration unnecessarily—the standard 2-3 day course covers the window for biphasic reactions without requiring tapering 1, 2. Longer courses increase side effects without additional benefit for simple allergic reactions 2.

Do not discharge patients prematurely—observe for minimum 4-6 hours after anaphylaxis, with longer periods for severe reactions, airway involvement, or patients requiring multiple epinephrine doses 1.

Recognize that corticosteroids alone will not prevent all biphasic reactions—up to 20% may still occur despite treatment, emphasizing the importance of patient education, epinephrine auto-injector prescription, and allergist follow-up 1, 2.

Special Populations

Patients on Beta-Blockers:

• May be refractory to epinephrine and require glucagon 1-5 mg IV over 5 minutes 1
• Standard prednisone dosing still applies as adjunctive therapy 1

Elderly or Patients with Comorbidities:

• Consider drug interactions and conditions exacerbated by corticosteroids (diabetes, hypertension, osteoporosis) 2
• Standard dosing typically applies, but monitor closely for adverse effects 2

Asthmatic Patients:

• May require higher doses and longer duration: 30-60 mg daily for 1-3 weeks for asthma-related allergic reactions 2
• These patients are at higher risk for severe reactions and should receive corticosteroids more liberally 1