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What happens in an allergic reaction?
When hayfever sufferers inhale pollen, they produce special antibodies that stick to the pollen grains. These clumps then stick to cells lining the nose, throat and lungs, causing a sudden release of chemicals, including histamine, by the body. This 'red-alert' signal usually switches on only when the body is infected or injured. It triggers inflammation, which causes the symptoms of hayfever.
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