How Long Does Fexofenadine Take To Work?

Fexofenadine, also known as Allevia, Telfast, and Treathay, is a type of antihistamine used to treat allergy symptoms. Most people find that fexofenadine takes effect within 1 to 2 hours of taking it, providing fast and effective relief from hay fever, eczema, conjunctivitis, and other allergy symptoms.

If you experience allergy symptoms, you likely want to know how quickly you will feel relief when taking fexofenadine as your chosen antihistamine.

How long does fexofenadine take to work?

The average time it takes for fexofenadine to provide allergy relief is 2 hours. Some people may notice their symptoms subside within 10 to 20 minutes after taking a fexofenadine pill.

What affects how long it takes for fexofenadine to work?

Fexofenadine should not be taken with a high-fat meal, as it may affect the time it takes to work. High-fat meals reduce the concentration of fexofenadine in the bloodstream, meaning it can take 4 hours before you feel any relief.

You should also avoid the following food and drink when taking fexofenadine because it can increase the risk of side effects:

• grapefruit juice
• apple juice
• orange juice

What is fexofenadine for?

Fexofenadine is an antihistamine that’s used to treat hay fever symptoms, like:

• sneezing
• itchy nose
• runny nose
• blocked nose
• itchy, red, and watery eyes

Fexofenadine is also used to treat:

• eczema
• conjunctivitis
• hives
• some food allergies
• insect bites or stings

How does fexofenadine work?

Fexofenadine contains the active ingredient fexofenadine hydrochloride. It works by blocking the body’s histamine receptors to stop the effects of histamine from affecting you. Histamine is released by your immune cells when they detect an allergen, causing allergy symptoms when it binds to its receptors.

Because fexofenadine binds to the histamine receptors, histamine cannot cause any symptoms, so you should start to experience relief shortly after taking fexofenadine.

Does fexofenadine make you drowsy?

Fexofenadine is known as a non-drowsy antihistamine, which means it is less likely to cause drowsiness than other antihistamines. So, you may find fexofenadine more suitable if you work during the day, for example.

It is advisable to avoid alcohol when taking fexofenadine because it can affect your focus and make you feel drowsy.

Is fexofenadine available under any other names?

Yes, fexofenadine is available as a generic version, but branded fexofenadine medications are available, such as:

• Telfast
• Treathay
• Allevia

How do I know if I have hay fever?

Hay fever and colds share similar symptoms, making it challenging to distinguish between the two.

The symptoms of hay fever include:

• sneezing
• coughing
• itchy eyes
• runny or blocked nose
• headache
• itchy throat, mouth, nose, and ears

The symptoms of hay fever usually worsen between March and September when pollen counts are at their highest.

You can find out more about the difference between hay fever and a cold in our blog.

Fexofenadine alternatives

Fexofenadine may not be suitable for everyone. If you don’t think fexofenadine is right for you, Prescription Doctor has a range of hay fever treatments available:

• Beconase aqueous nasal spray: Contains a corticosteroid to reduce inflammation in your nose, making it easier to breathe.
• Cetirizine hydrochloride: Another type of non-drowsy antihistamine containing the active ingredient cetirizine hydrochloride. It’s also available under the brand names Benadryl Allergy, Piriteze Allergy Tablets, and Zirtek.
• Clarityn: Contains the active ingredient loratadine, an effective non-drowsy antihistamine.
• Piriton Allergy Tablets: These contain chlorphenamine maleate, a histamine receptor antagonist that can cause drowsiness.

Explore our range of hay fever treatments.

Summary

Fexofenadine is an effective antihistamine used to treat allergy symptoms, particularly those associated with hay fever. It works by blocking the body’s histamine receptors, providing relief from the irritating symptoms, including itchy eyes, a runny nose, and sneezing.

Typically, fexofenadine is taken once daily, and most people notice its effects within 2 hours of administration. Some people start to feel relief within the first 10 to 20 minutes, making fexofenadine a popular hay fever treatment.

Authored By

Leanne Edermaniger

Medical Content Writer

Leanne is a science and health content writer focusing on human health and biology while utilising her solid academic background.

Published on: 07/08/2024

Reviewed By

Mohamed Imran Lakhi

MPharm - Lead Pharmacist

Imran Lakhi is the superintendent pharmacist and founder at Prescription Doctor. He has been at the core of our team.

Reviewed on: 05/06/2025