It is spring and a little boy has terrible allergies. His nose is stuffed with mucus and he has a cough. Why are his mucous membranes producing so much mucus?

Mucus helps trap particles such as pollen before they can travel farther into the body. During an allergic reaction, the mucous membranes become irritated and produce extra mucus, which can cause a stuffy nose and cough. The mucus is responding to pollen, not to mucus itself, and it does not always increase in spring.

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