Fexofenadine Tablets

What is fexofenadine?

Fexofenadine an antihistamine used to treat allergy and hay fever symptoms. It's classed as a non-drowsy antihistamine, meaning it’s less likely to make you feel sleepy.

What is fexofenadine used for?

Fexofenadine 120mg can be used to treat:

• hay fever

• pet allergies

• some food allergies

• eczema

• hives (though 180mg is more effective)

• insect bites and stings

• allergic conjunctivitis

How does fexofenadine work?

Fexofenadine is an antihistamine, which means it works by blocking a substance called histamine that your body releases during an allergic reaction.

When you come into contact with an allergen, your body releases histamine, causing allergy symptoms like itchy eyes and a runny nose.

By taking fexofenadine, histamine isn’t able to cause inflammation, and your symptoms can be relieved and prevented.

How long does fexofenadine take to work?

Fexofenadine usually takes around an hour to work and will stay in your system for up to 24 hours.

How effective is fexofenadine?

Fexofenadine is very effective at treating allergy symptoms. One clinical study actually found it was more effective than loratadine at treating itchy, watery, red eyes and nasal congestion, and was less likely to cause drowsiness than cetirizine.

How to take fexofenadine 120mg

You should always read the patient information leaflet before taking fexofenadine.

Fexofenadine 120mg can be taken by adults under the age of 65 and children aged 12 and over.

The usual dose for hay fever in adults and children aged 12 years and over is one 120mg tablet, once a day.

You should take your fexofenadine tablet before a meal, swallowed whole with a drink of water.

When to take fexofenadine

When to take fexofenadine depends on your condition. You should speak to your clinician for expert advice.

You might only need to take this medicine when you have symptoms triggered by exposure to an allergen.

If you regularly suffer from hay fever, you might need to take fexofenadine regularly throughout hay fever season to prevent your symptoms.

Fexofenadine side effects

Like all medications, fexofenadine can have side effects, although not everyone will experience them. The most common side effects include:

• headaches

• drowsiness

• nausea

• dry mouth

• dizziness

For a complete list of side effects, please refer to the patient information leaflet included with your medication. And for more information about reporting the side effects of medication, please see the MHRA’s Yellow Card Scheme.

If you experience a fast or irregular heartbeat after taking fexofenadine, you should seek medical attention as soon as possible.

If you experience any symptoms of anaphylaxis (difficulty breathing, swelling in the face and mouth, skin rash) after taking fexofenadine, you should call an ambulance or go to your accident and emergency department immediately.

Driving and fexofenadine

As fexofenadine is a non-drowsy antihistamine, you will usually be able to drive when you’ve taken it. However, there is still a possibility that you will feel sleepy or drowsy after taking this medication.

We recommend first taking this medication at a time when you will not need to drive or use any machinery, as this will give you the chance to assess the effect this treatment has on you and work out whether you would be able to drive safely.

If you do feel drowsy, dizzy, or like your concentration or vision have been affected in any way after taking this medication, then you should not attempt to drive or use machinery until these side effects have passed.

Fexofenadine and alcohol

You should avoid drinking alcohol as much as possible while you’re taking fexofenadine or any other antihistamines. Alcohol can make side effects like drowsiness more likely.

When to avoid fexofenadine

You should avoid fexofenadine if you’ve ever had an allergic reaction to this medicine in the past. You should also let your clinician know if you have ever had an allergic reaction to any other medicines before.

You should speak to your clinician before taking fexofenadine if:

• you have problems with your liver or kidneys

• you have, or have ever had, heart problems

• you have epilepsy or another condition that puts you at risk of seizures

• you are booked in for an allergy test

Fexofenadine and pregnancy

You should not take fexofenadine when you’re breastfeeding and usually will not be able to take it during pregnancy. You can find out more about treating hay fever in pregnancy in our expert guide.

Fexofenadine and other medications

Talk to your clinician before taking fexofenadine if you are on the following:

• upset stomach medications which contain aluminium or magnesium, e.g. antacids like magnesium carbonate or aluminium hydroxide

• erythromycin or rifampicin

• ketoconazole

• midodrine

• ritonavir or lopinavir

• any medications or herbal remedies which make you drowsy, cause dry mouth, or make it difficult for you to pee

• any other antihistamines

You should also avoid drinking grapefruit juice, orange juice and apple juice while taking fexofenadine. These juices can interfere with the absorption of fexofenadine into the body, making it less effective.

How to store fexofenadine

Store in a cool, dry place which is out of direct sunlight. Do not use this product if the expiry date printed on the original packaging has passed. Keep out of sight and reach of children.

Alternatives to fexofenadine

If fexofenadine isn’t working for you, there are a range of other options you can try. Other non-drowy antihistamines include cetirizine (Piriteze) and loratadine (Clarityn).

If your allergies are bothering you at night, you could consider a drowsy antihistamine like promethazine (Phenergan) and chlorphenamine (Piriton).

There are also more targeted options like Dymista nasal spray or Optrex eye drops.

Sources

• About fexofenadine. NHS. [Accessed 24 February 2026].

• Fexofenadine Patient Information Leaflet. [Accessed 24 February 2026].

• Efficacy and safety profile of fexofenadine HCL. (2003.) The Journal of Allergy and Clinical Immunology. [Accessed 24 February 2026].