As we head deeper into spring and the prospect of summer comes tantalisingly close, many people will be celebrating the improved weather, the longer days and lush greenness that comes with the warmer months. But thousands of other people will be slightly more apprehensive about the onset of summer as the pollen count climbs and we enter into the worst period for hay fever sufferers.

It's estimated that there are more than 10 million people with hay fever in England. Yet understanding of the condition is not widely known. Hay fever is an allergic reaction caused when the body's defences overreact to a perceived threat. When a hay fever sufferer comes into contact with pollen the immune system reacts with the same severity as it would if confronted with a virus. The result is a release of chemicals to stop what the body believes to be an infection.

In real terms, these chemicals are released when pollen comes into contact with the lining of the mouth or nose and aggravates the cells. It is the response of the body's own immune system that causes the symptoms we commonly associate with hay fever - such as congestion, sinus pressure, a runny nose, watery eyes, swelling and increased asthmatic reactions.

So what is the pollen that causes such a strong reaction in those with a sensitive nose? Pollen is produced by male plants as a form of asexual reproduction, and it will usually be picked up by the wind or various insects before being deposited on female plants. This is called pollination, and is what allows seeds to grow. However, the release of pollen into the air also increases the likelihood of it coming to contact with humans - resulting in an allergic reaction.

There are around 30 different types of pollen that are known to cause hay fever. These fall into three broad categories: grass pollen, tree pollen and weed pollen. Grass pollen is the most common cause of hay fever in the UK and affects 90% of sufferers, while tree pollen hits 25% of those with hay fever. The pollen released by weeds such as mugwort and nettles can also cause a reaction but it is the rarest of the three categories.

As the time when plants are at their most active, the spring and summer months are when hay fever sufferers are at the greatest risk of falling foul of classic symptoms such as a runny nose and itchy eyes. In particular, the grass pollen count is at its highest from mid-May through to July.

Fortunately, there are a range of hay fever treatments currently on the market. Many of these come in tablet form, such as the antihistamines Fexofenadine and Telfast. Antihistamines provide fast relief in the event of a reaction and can counteract the worst of the symptoms by preventing the release of the chemicals that the body uses to fight pollen. Corticosteroid nasal sprays like Nasonex and Mometasone can also get to the root of the problem quickly, soothing the symptoms of hay fever. A pharmacist may even recommend the use of a nasal spray as a preventative measure.

It is important to always pay attention to the usage instructions outlined by your pharmacist and on the packet before using either tablets or nasal sprays. Taking a higher dosage can increase the likelihood of side effects such as drowsiness, nose bleeds and headaches.

If you've been suffering from hay fever and want to find the right course of treatment for you, then speak to your pharmacist for expert advice. Don't let hay fever ruin your Summer, take back control with the help of your pharmacist today.