Fexofenadine

Class: Second-generation antihistamine (H1-receptor antagonist)

Indications: Allergic rhinitis, chronic idiopathic urticaria

Mechanism: Selectively blocks peripheral H1-receptors, reducing histamine-mediated allergic symptoms with minimal sedation.

Dosage

• Adults & ≥12 yrs: 120 mg once daily or 180 mg once daily
• Children 6–11 yrs: 30 mg twice daily
• Children 2–5 yrs: 30 mg once daily
• Children 6 mo–2 yrs: 15 mg twice daily (for urticaria)
• Max dose: 180 mg/day

Major Side Effects

• Headache
• Dizziness
• Nausea
• Occasional drowsiness (rare compared to first-gen antihistamines)

Contraindications

• Known hypersensitivity to fexofenadine or any component
• Severe renal impairment (use with caution, dose adjustment needed)

Compatible Solvent / Administration

• Oral tablets, suspension (administer with water, not fruit juice)

Special Precautions

• Avoid grapefruit, orange, and apple juice (reduces absorption)
• Caution in patients with renal insufficiency
• Generally non-sedating, but caution if used with other CNS depressants
• Pregnancy Category C – use only if clearly needed