Hayfever Treatments | How Do Antihistamines Work?

Hayfever is common in Ireland, especially throughout the summer season and antihistamines are often the first port of call to prevent and treat hayfever. But

do you know which antihistamines to take and which ones are more likely to cause side effects?

The Root Cause of Hayfever

Hayfever is an allergy to pollens, most commonly from grasses and trees. When these pollens come into contact with the tissue inside the nose, they trigger an immune reaction that can cause the following symptoms:

• mild sneezing to severe coughing
• blocked or clogged nose
• watery, red, and itchy eyes
• itchy mouth, throat, and ears
• temporary absence of smell
• pain in the forehead and temple
• ear inflammation
• exhaustion and dehydration

Symptoms typically return for the hayfever season each year. Hayfever is commonly worse from late March and September. However, when the season is humid, warm, and windy, pollens spread all over the nearby cities. Hayfever may last for weeks or months, unlike a cold, which normally goes away after 1 to 2 weeks.

You should limit your exposure to substances that leads to hayfever as much as possible. If your hayfever isn’t too severe, you could take over-the-counter medications to alleviate the symptoms. 

You may need prescribed medications for more severe symptoms. However, the best relief is to prevent and reduce the amount of allergen you come into contact with.

Not all hayfever medications are suitable for use in children or people who are taking other medications so please talk to your local Brennan’s Pharmacy team if you need advice. 

How to Reduce Hayfever Symptoms

Currently, there is no fast and reliable cure for hayfever. However, there are treatments available from Brennans Pharmacy that will prevent, reduce and ease your symptoms when the pollen count is high.

Some simple lifestyle changes can reduce the impact of hayfever on your life. For example, you could:

• Put Vaseline all over your nostrils to trap pollen
• Wear the recommended sunglasses to prevent pollen or other dust particles from entering your eyes
• Ensure to change your clothes and take a bath regularly to wash pollen particles
• Stay indoors when possible
• Keep windows and doors shut
• Vacuum often
• Dust your furniture or any belongings with a damp cloth when you exposed to pollen
• Purchase a pollen filter with HEPA for your car and vacuum

Conversely, it would help NOT TO DO the following:

• Cut grass or walk on grass
• Spend too much time outside
• Keep fresh flowers in the house
• Smoke or be around smoke makes your symptoms worse.=
• Dry clothes outside, they can catch pollen
• Let pets get inside the house if possible; they can carry pollen indoors

If you are still suffering, there is a wide range of hayfever treatments available directly from your local Brennan’s Pharmacy.

What Are Antihistamines Used For?

Antihistamines are commonly used to treat and reduce the severity of allergic reactions to dust, pollen, and air particles. Antihistamines remain the most common relief against the symptoms of allergies such as hayfever. 

They are also commonly used to reduce the itchiness of hives, conjunctivitis, and reactions to insect bites or stings. Most antihistamines are available from pharmacies and shops, but some require a prescription. Some antihistamines also cause drowsiness and therefore, those antihistamines may not be the best choice for some people.

They can also be used for other problems such as:

• Sneezing
• Itching of the eyes, nose, and throat
• Runny nose (rhinorrhoea)
• Reduce the rashness, itching, and redness linked with nettle rashes
• Motion sickness and nausea
• Morning sickness for pregnant women 
• Terminal illness and sedation 

How Do Antihistamines Work?

Antihistamines work to stop the effects of histamine, a chemical that is normally released when your body detects a harmful substance. When histamine is released it causes the blood vessels to expand, your skin swell, and the symptoms commonly associated with hayfever to occur.

In people affected with hayfever, the body mistakenly detects something harmless like grass pollen as harmful and causes histamine to be released in response which then leads to the common hayfever symptoms.

If you take antihistamines before you come into contact with the allergen it can prevent any reaction from occurring or you can reduce the severity of the symptoms by taking them afterward. 

Which Are The Best Antihistamines?

There’s not enough evidence to suggest any particular antihistamine is better than any other at relieving allergy symptoms. Some people find certain types that work well for them, and others do not. Some older version of antihistamines causes drowsiness which might also affect your decision.  Ask our pharmacy team for advice if you’re unsure which medicine to try. 

For hayfever, taking an antihistamine tablet may not be enough by itself. You may also need eye drops and/or a nasal spray to sort out all your symptoms. Please refer to Brennan’s pharmacy for more hayfever treatment medications.

Antihistamines only work for a short duration of time, so you need to take them on a daily basis to ensure they are effective.

Which Antihistamines Cause Drowsiness?

Antihistamines have been typically classified into two groups.

First-generation or sedating antihistamines

These antihistamines can cause significant drowsiness associated with antimuscarinic side effects such as dry mouth and urinary retention. These antihistamines are useful for treating conditions due to symptoms of urticaria or atopic dermatitis. Alimemazine and promethazine appear to be most sedating. The most well-known of these antihistamines are promethazine (Phenergan) and chlorphenamine (Piriton).

Non-sedating or second-generation antihistamines

Second-generation or non-sedative antihistamines either cause little or no drowsiness. However, when combined with other sedating medications or alcohol they can still cause additional effects so caution should be taken by those in these groups. The drowsiness effects can vary from person to person so it’s important to be cautious until you take them yourself. Not only are they less sedating but you are also less likely to experience any antimuscarinic side effects with these antihistamines. The most common ones from this class of antihistamines found in pharmacies in Ireland are cetirizine (Zirtek) and loratadine (Claritin).

Don’t Forget 

The team at Brennan’s Pharmacy are here to answer your questions and provide advice so you can choose the best medicine for you. Just because one medicine works for someone else, does not mean it is suitable for you. Always read the label or package leaflet before taking any medication. If you are unsure about purchasing any product get in touch with our team online or call any of our pharmacy stores directly.