Hayfever, also known as seasonal allergic rhinitis, affects a lot of people across the UK each year, especially during spring and summer.
It tends to show up when pollen levels rise and the immune system reacts more strongly than needed.
For many people, tablets are one of the first options they try for allergy relief across the UK, yet how they actually work is not always clear.
This guide explains how hayfever tablets work, the role antihistamines play, why some tablets cause drowsiness while others do not, and how to take them properly.
The aim is to help you understand hayfever symptoms and treatment so you can make informed choices if allergies start to interfere with daily life.
What Causes Hayfever Symptoms
Hayfever symptoms start when the body mistakes pollen for something harmful.
Grass, tree, or weed pollen enters the nose, eyes, or throat, and the immune system responds as if it is under threat. This reaction is not dangerous, but it can feel uncomfortable and disruptive.
The immune system releases chemicals designed to protect the body. One of the main chemicals involved is histamine. This response leads to familiar symptoms such as sneezing, a runny or blocked nose, itchy eyes, and throat irritation.
Understanding this process helps explain why certain medicines are used to manage hayfever symptoms and treatment rather than remove the cause itself.
The Role of Histamine in Allergies
Histamine plays a central part in histamine and allergies. When pollen triggers the immune system, histamine is released into nearby tissues. It causes blood vessels to widen and become more permeable, which leads to swelling, redness, and increased mucus production.
In the nose, this results in congestion and sneezing. In the eyes, it causes itching and watering. In the throat, it can lead to irritation and coughing.
These effects are the body’s attempt to flush out what it believes is a harmful substance. Blocking the action of histamine is therefore a key approach to reducing allergy symptoms.
How Antihistamine Tablets Reduce Symptoms
Antihistamine tablets work by blocking histamine from attaching to its receptors in the body. When histamine cannot bind to these receptors, its effects are reduced. This is why antihistamines for hayfever can help ease sneezing, itching, and a runny nose.
These tablets do not stop the immune system from reacting to pollen, and they do not remove pollen from the air. Instead, they limit how strongly histamine affects the body.
This is an important distinction, as antihistamines manage symptoms rather than act as a cure. People may still notice mild symptoms during high pollen periods, even when taking tablets correctly.
First Generation vs Second Generation Antihistamines
Not all antihistamines act in the same way. They are usually grouped into first-generation and second-generation antihistamines based on how they behave in the body.
First-generation antihistamines have been used for many years. They block histamine effectively but can also enter the brain. This is why they are more likely to cause drowsiness and reduced concentration. Some people find this helpful at night, while others avoid them during the day.
Second-generation antihistamines were developed to target histamine receptors more selectively. They are designed to stay largely outside the brain, which lowers the chance of sedation. These are commonly described as non-drowsy allergy medications, although mild tiredness can still occur in some people.
| Feature | First generation | Second generation |
| Drowsiness | More likely | Less likely |
| Duration | Shorter acting | Longer lasting |
| Typical use | Night-time relief | Daytime symptom control |
When people search for the best hayfever tablets, it usually reflects personal response rather than one option being better for everyone.
How Quickly Hayfever Tablets Start Working
Most antihistamine tablets begin to take effect within thirty to sixty minutes. The exact timing can vary depending on the type of tablet, whether it is taken with food, and how your body absorbs medication.
For ongoing symptoms, regular daily use during pollen season tends to work better than taking tablets only after symptoms become severe.
Starting treatment before peak pollen exposure may help keep symptoms more manageable, especially for those who experience strong reactions each year.
Possible Side Effects of Hayfever Tablets
Like all medicines, hayfever tablets can cause side effects, although many people experience none at all.
Common side effects may include:
- Feeling sleepy or less alert
- Dry mouth or dry eyes
- Mild headache
Less common effects can include:
- Dizziness
- Feeling sick
- Stomach discomfort
If side effects feel persistent or troublesome, it is sensible to stop taking the tablets and seek advice from a healthcare professional. This is particularly relevant if symptoms interfere with work, driving, or daily activities.
Taking Hayfever Tablets Correctly
Knowing how to take hayfever tablets properly can make a real difference to how well they work.
- Take the tablet at the same time each day to maintain steady levels in the body
- Follow the instructions on the packaging regarding food
- Avoid alcohol if using tablets that may cause drowsiness
- Do not take more than one antihistamine at the same time unless advised
Consistency matters during pollen season, especially for people who experience symptoms most days.
When to Consider Prescription Hayfever Treatments
For some people, over-the-counter tablets do not provide enough relief. This can happen when symptoms are severe, last for long periods, or affect sleep and concentration.
In these cases, a healthcare professional may suggest other approaches, such as prescription-strength treatments or nasal sprays, based on individual needs.
If hayfever continues to disrupt daily life despite using tablets correctly, it may help to explore your options for hay fever treatments with professional guidance. You can also contact us to discuss symptoms and understand what support may be available through a consultation.
