Hay fever is an allergic reaction to certain things. Common triggers include pollen, ragweed, and cats. Also known as allergic rhinitis, there are two types: seasonal, which happens only during ...

Hay fever occurs when your immune system overreacts to an outdoor allergen, such as pollen. An allergen is something that triggers an allergic response. The most common allergens are pollens from ...

And with pollen comes hay fever, which can mean a runny nose and itchy eyes for many people, especially if you're outside more often in the sunny weather. According to the Met Office, which is the ...