Asked by: Joe Chesterman-March, by email
Hay fever is an excessive immune response to the pollen particles in the air. Your body attempts to fight off what it perceives as an invader by releasing histamine into your bloodstream. The cells lining your nose and eyes respond to histamine by streaming, to flush themselves out. Hay fever tablets contain antihistamine, which binds to the histamine receptors in your body and prevents them from reacting to the histamine.
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