Allegra (Fexofenadine HCl)

What you should know about before taking Allegra.

Medication Warning Label
Medication Warning Label. Julia Nichols/Getty Images

What is Allegra?:

Allegra is an antihistamine used to treat allergies caused by pollen, dust mites, dander, etc. Allegra helps to control the symptoms of these conditions such as runny nose (rhinitis), itchy eyes, and some allergic skin conditions such as hives.

Who Can Take Allegra?

Most healthy individuals over the age of two can take Allegra if they have never had an allergic reaction to fexofenadine hydrochloride.

You shouldn't take Allegra if you are pregnant or nursing without talking to your doctor and/or pharmacist first. Allegra ODT cannot be taken by individuals who have a condition known as PKU (phenylketonuria) because this particular form of the medication contains phenylalanine. Allegra can interact with other medications you may be taking so you need to discuss all of your medications with your doctor before adding Allegra to your medication regime.

How Is Allegra Taken?

Allegra only comes in oral formulations including: oral tablets, ODT or oral dispersible tablets (disintegrates under the tongue or in liquid), and a liquid suspension. The prescribed dose may vary based on the reason for the medication. Normal doses include:

  • Child: 6 months to < 2 years = 15 mg twice a day
  • Child: 2 to 11 years old = 30 mg twice a day
  • Child > 12 or Adult = 60 mg twice a day or 180 mg once a day

The right dose for you might vary, so make sure you read the instructions on the bottle carefully and check with your doctor if you're not sure how much to take.

With the exception of the ODT formula, Allegra can be swallowed with a glass of water. Do not take Allegra with fruit juice or antacids. 

What Are Side Effects of Allegra?

Allegra can cause the following side effects:

  • fatigue
  • drowsiness
  • headache
  • cough
  • upper respiratory infections
  • vomiting
  • diarrhea
  • stomach ache

The following side effects could indicate a life-threatening allergic reaction and should be reported to emergency medical personal (911) right away: swelling of the face or tongue, difficulty breathing or swallowing, or wheezing.

Additional Warnings:

Keep this medication out of the reach of children. If an overdose occurs contact the poison control center or emergency medical services immediately.


Aventis Pharmaceuticals, Inc. (n.d.) Allegra (fexofenadine hydrochloride). Accessed on November 3, 2015 from,20872se8-011,20625se8-012_allegra_lbl.pdf . (2015). Fexofenadine: Drug Information. Accessed on November 3, 2015 from

Continue Reading