How do antihistamines work?

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What are Antihistamines?

Antihistamines are used by allergy sufferers to relieve allergy symptoms from seasonal and year-round allergies.

What types of antihistamines are there?

Two types of antihistamines are used for allergies. They are known as first-generation and second-generation antihistamines.

First-generation antihistamines

First-generation antihistamines, like chlorphenamine, were developed back in the 1940s and have been providing symptom relief to millions of people ever since. They are characterised by their ability to block the action of histamine, which is heavily involved in the body’s allergic response. However, first-generation antihistamines pass through the blood brain barrier and can cause side effects such as drowsiness and impair cognitive function. Some adults may use these medicines over a short-term for the drowsiness effect under the advice of a doctor or pharmacist particularly where allergic symptoms such as runny or congested nose affect sleep.1

Second-generation antihistamines

Second-generation antihistamines, such as Fexofenadine only cross the blood-brain barrier minimally and thus are unlikely to cause drowsiness in most people compared to first-generation antihistamines.

Can antihistamines cure my allergies?

Antihistamines can’t cure allergic conditions, but they can provide much-needed relief from the symptoms of:

  1. Hayfever (seasonal allergic rhinitis) — This common allergic condition can cause sneezing, runny nose, inflammation of nose and eyes, and itching of eyes, nose and throat.
  2. Perennial allergic rhinitis – non-seasonal allergic rhinitis can also be triggered by pet dander, dust mites and mould spores which can be present all year round

How do antihistamines work?

As the name suggests, antihistamines work by stopping the effects of histamine. Histamine is a chemical substance released by the body’s immune system as a response to an allergen. In an allergic reaction, too much histamine is released, leading to symptoms such as a runny nose, itchy eyes and swelling.

How do I choose an antihistamine?

Your doctor or pharmacist may advise a particular antihistamine, depending on the type and cause of your allergy.

Where can I buy antihistamines?

Several antihistamines are available over the counter at your pharmacy without a prescription. Talk to your pharmacist to work out which antihistamine would be best for you.

What is Allevia?

Allevia is a second-generation antihistamine, which means it is less likely to cause drowsiness than first-generation antihistamines. Allevia can help to manage the symptoms of hayfever allergies and year-round allergic rhinitis.
Always read the label and follow the directions for use.

How does Allevia work?

Allevia contains 120mg of the active ingredient fexofenadine hydrochloride.

Fexofenadine acts within 1 hour without causing drowsiness in most people to help relieve the symptoms of airborne allergies by blocking histamine receptors in the body.

Allevia 120mg can be taken daily for relief from allergy symptoms caused by pollen, pet dander, dust mites and mould. As allergy symptoms often peak in the morning2, treatments that work within 1 hour such as Allevia can help provide relief from allergies when you need it most and lasts all day.

Why should I use Allevia for my allergy symptoms?

  • Allevia 120mg works within an hour of taking it for much needed relief from allergy symptoms.
  • The active ingredient fexofenadine is a second-generation antihistamine that does not cause drowsiness in most people.
  • 24 hour symptom relief – Allevia 120mg provides a convenient one-a-day tablet for 24-hour relief.
  • Multi-symptom relief – Allevia provides relief from the multiple symptoms of allergic rhinitis including sneezing, runny nose and nasal congestion.
  • May be used every day – Allevia may be used every day to help provide relief from airborne allergies such as pollen, dust, mould and pet dander.

Why should you take Allevia?

Allevia is used in adults and adolescents over 12 years of age to relieve the symptoms of allergic rhinitis (for example hayfever) such as sneezing, itchy, runny or blocked nose and itchy, red and watery eyes.

For allergy sufferers who want action within 1 hour, is non-drowsy in most people and lasts for 24 hours, consider Allevia 120mg.

Who should not take Allevia 120mg?

If you are pregnant or breastfeeding please check with your GP or a pharmacist before use.

How should I take Allevia?

The recommended dose of fexofenadine hydrochloride for adults is once daily taken before a meal. Take with water to facilitate administration.

Always read the label and follow the directions for use.

Take Allevia before your symptoms take over you

Life isn’t waiting for your allergy symptoms to pass and neither should you.

That’s why Allevia® helps deliver relief that lasts 24 hours, acts within one hour and is prescription strength, so you can get on with enjoying your day.​

Get the relief that's right for you with Allevia