All medications

Fexofenadine

Allergy

Also known as Allegra

Fexofenadine is a non-drowsy antihistamine — it blocks histamine, the chemical behind sneezing, itching, and runny nose. It's the least sedating of the common allergy pills, which makes it a good pick if other antihistamines make you foggy. The one thing to know: fruit juice genuinely interferes with how your body absorbs it, so what you swallow it with actually matters.

How to take it

When

Take it as the label or your doctor directs — some versions are once a day, others twice.

Food

Take it with plain water only. Orange, apple, and grapefruit juice cut down how much your body absorbs, so skip juice within a few hours of your dose.

Avoid

Don't take it at the same time as antacids that contain aluminum or magnesium — space them apart by a couple of hours.

Good to know

It's the least likely of the big three allergy pills to make you drowsy, so it's a favorite for people who drive or operate machinery.

Missed a dose?

If you take it on a schedule and miss a dose, take it when you remember. If it's close to your next dose, skip the missed one. Never double up.

Common side effects

  • Headache
  • Nausea
  • Dizziness (uncommon)
  • Cold-like symptoms such as cough or back discomfort

Call a doctor if

Educational only. This summary is drawn from public FDA labeling and MedlinePlus and simplified for readability. Your prescription label and your pharmacist always come first — doses and instructions vary from person to person.