Fexofenadine (Allegra) — what it helps with and how to use it

Fexofenadine is a second‑generation antihistamine many people use for seasonal allergies and chronic hives. It works by blocking histamine, the chemical that causes sneezing, itch, runny nose, and red, itchy skin. Unlike older antihistamines, fexofenadine usually causes little or no drowsiness for most users.

Common uses and how fast it works

People reach for fexofenadine for hay fever symptoms (sneezing, itchy eyes, runny nose) and for relief from hives (urticaria). Many users feel relief within an hour, and the effect can last about 12–24 hours depending on the dose. For everyday allergy control, either a once‑daily or twice‑daily schedule is typical — follow the product label or your doctor’s advice.

Typical dosing, safety tips, and interactions

Adult dosing commonly is 60 mg twice a day or 180 mg once daily. Children’s doses change with age and product form, so always check the package or ask a pharmacist before giving it to kids. Don’t exceed the recommended dose. If you have kidney problems, your doctor may lower the dose.

Take fexofenadine with plain water. Avoid taking it with fruit juices (orange, apple, grapefruit) — they can cut how much drug your body absorbs. Antacids that contain aluminum or magnesium can also reduce absorption if taken at the same time; separate them by a couple of hours. Tell your doctor about other medicines you take — some antibiotics or antifungals can change fexofenadine levels.

Common side effects are mild: headache, dry mouth, or occasional drowsiness. Serious reactions are rare, but stop the drug and see a doctor if you get trouble breathing, severe rash, or swelling of the face or throat. If fexofenadine makes you sleepy, avoid driving or operating heavy machinery.

Fexofenadine is available over the counter in many countries, but rules differ. If you’re pregnant, breastfeeding, or have chronic health problems, check with your healthcare provider before starting it. Also mention if you’ve had drug allergies in the past.

Looking for alternatives? Cetirizine and loratadine are other non‑sedating antihistamines to consider; each has small differences in onset and side effects. If symptoms persist despite treatment, see a clinician — you might need a different drug, a higher level of care, or allergy testing.

Quick checklist: follow the label dose, take with water (not juice), separate from antacids, be cautious with kidney disease, and talk to your provider if pregnant or on other meds. That keeps fexofenadine safe and effective for everyday allergy relief.