What causes hayfever?
hayfever is an allergic reaction to airborne substances such as pollen and spores that get into the upper respiratory passages – the nose, the throat and the eyes. Once in contact with pollen, your body produces antibodies which stimulate cells to release chemicals such as histamine which then trigger an allergic response. In the nose, the tissues swell and causing the typical hayfever symptoms. In the UK, up to 25% of the population are affected, with around 90% of hayfever sufferers allergic to grass pollen.
