Recommended Starting Dose of Allegra (Fexofenadine) for Adults and Children Over 12 Years
The recommended starting dose of Allegra (fexofenadine) for adults and children 12 years and older is 60 mg twice daily or 180 mg once daily with water. 1
Dosage Guidelines
Standard Dosing
- Adults and children ≥12 years:
- 60 mg twice daily OR
- 180 mg once daily
Special Populations
- Patients with decreased renal function:
- Starting dose should be reduced to 60 mg once daily 1
Indications and Dosing by Condition
Seasonal Allergic Rhinitis
- Standard dose: 60 mg twice daily or 180 mg once daily
- Duration: As needed during allergy season
Chronic Idiopathic Urticaria
- Standard dose: 60 mg twice daily or 180 mg once daily 1
- Clinical trials have shown that doses of 60 mg twice daily or greater are most effective for urticaria symptoms 2, 3
Administration Considerations
- Take with water
- Can be taken without regard to meals
- No dosage adjustment needed based on age alone for adults and adolescents over 12 years
- No tapering required when discontinuing
Safety Profile
Fexofenadine offers several advantages that make it an excellent choice for allergy treatment:
- Non-sedating: Unlike some other antihistamines, fexofenadine is truly non-sedating with no dose-related increase in sedation, even at high doses 4
- No cardiac effects: Fexofenadine is not associated with cardiotoxicity or QT interval prolongation 5
- Blood-brain barrier: Does not penetrate the blood-brain barrier, which explains its non-sedating properties 6
- Side effect profile: Similar to placebo in clinical trials, with the most common adverse events being headache, throat irritation, and nausea 5
Common Pitfalls to Avoid
- Confusion with other antihistamines: Unlike some antihistamines that require once-daily dosing only, fexofenadine can be administered either once or twice daily depending on the selected dose
- Renal function assessment: Always assess renal function before prescribing, as patients with decreased renal function require dose adjustment
- Drug interactions: While fexofenadine has few clinically significant drug interactions, be aware that antacids containing aluminum or magnesium should be taken at least 2 hours apart from fexofenadine
Efficacy Considerations
Clinical trials have demonstrated that fexofenadine effectively controls symptoms of seasonal allergic rhinitis and chronic idiopathic urticaria. For urticaria specifically, studies have shown that doses of 60 mg twice daily or greater provide optimal symptom relief 2, 3.