Indications

Allergic Rhinitis: Relief of sneezing, rhinorrhea, lacrimation, itchy/red eyes, itchy nose/palate/throat in adults and children ≥12 years. Improves quality of life and productivity.
Chronic Idiopathic Urticaria: Relief of pruritus, wheals, and severity of symptoms in adults and children ≥12 years. Improves quality of life and daily activity.

Pharmacology Fexofenadine is an inverse agonist of the H1 receptor. It stabilizes the inactive form, preventing histamine activation. Highly selective for H1 receptors, does not cross the blood‑brain barrier, and has no sedative or anticholinergic effects.

Dosage & Administration

Adults & ≥12 yrs: 60 mg twice daily or 120 mg once daily.
Children 6–11 yrs: 30 mg twice daily.
Children 2–11 yrs (suspension): 30 mg (5 ml) twice daily.
Children 6 months–2 yrs (suspension): 15 mg (2.5 ml) twice daily.
Renal impairment: Reduce to once daily.

Interactions No hepatic metabolism. Erythromycin/ketoconazole increase plasma levels but no QT effect. Antacids (Al/Mg hydroxide) reduce absorption → separate by 2 hours.

Contraindications Hypersensitivity to fexofenadine or excipients.

Side Effects Common: Headache, drowsiness, dizziness, nausea. Uncommon: Fatigue. Rare/Post‑marketing: Hypersensitivity (angioedema, chest tightness, dyspnea, flushing, anaphylaxis), insomnia, nervousness, tachycardia, palpitations, diarrhea, rash, urticaria, pruritus.

Pregnancy & Lactation Limited human data. Avoid unless necessary. Excreted in breast milk → not recommended during breastfeeding.

Precautions & Warnings Use cautiously in elderly, renal impairment, or cardiovascular disease. Generally does not impair driving or machinery use, but individual response should be checked.

Special Populations

Renal impairment: Start at 60 mg once daily.
Hepatic impairment: No major effect.
Elderly: Increased bioavailability; monitor closely.

Overdose Effects Symptoms: Dizziness, drowsiness, fatigue, dry mouth. High doses tolerated without serious adverse events. Hemodialysis ineffective; supportive care recommended.