Fexofenadine

Fexofenadine is a non-sedating antihistamine for allergic rhinitis and chronic urticaria. As the active metabolite of terfenadine, fexofenadine provides effective antihistamine action without the cardiac risks that led to terfenadine's withdrawal. It does not cross the blood-brain barrier significantly, making it one of the least sedating antihistamines available. Generic fexofenadine is bioequivalent to branded Telfast.

How to Take Fexofenadine

Take fexofenadine 120 mg or 180 mg once daily with a glass of water. It can be taken with or without food, but avoid taking it with fruit juices (particularly grapefruit, orange, and apple juice) — these significantly reduce how much fexofenadine is absorbed into the bloodstream. Water is the best choice.

Fexofenadine is a non-drowsy antihistamine with an effect that lasts a full 24 hours. Take it at the same time each day for consistent symptom control. For seasonal allergies, starting a few days before the pollen season begins can help establish a protective level before symptoms start.

Daily Prevention

Fexofenadine works best when taken every day rather than only when symptoms are already present. It is safe for long-term daily use and does not lose its effectiveness with continued treatment.

Allergic rhinitis: 120 mg once daily. Chronic urticaria: 180 mg once daily.

Common Side Effects

Fexofenadine is one of the least sedating antihistamines available. Side effects are uncommon:

• Headache
• Drowsiness (rare at recommended doses)
• Nausea
• Dizziness

Interactions to Be Aware Of

Fruit juices (grapefruit, orange, apple) reduce the absorption of fexofenadine by up to 70% and should be avoided around the time of the dose. Antacids containing aluminium or magnesium (such as some indigestion remedies) should also not be taken at the same time as fexofenadine, as they reduce absorption. Space any antacid dose by at least two hours before or after fexofenadine.

Fruit juices (orange, grapefruit, apple) can reduce absorption by up to 36%. Take with water. Dose adjustment may be needed in renal impairment.

Contraindicated in known hypersensitivity to fexofenadine.