Why do your eyes water when your nose is hit?

Wednesday 22nd July 2009
Submitted by Luis Villazon
Joshua Smith

The nose is soft and sensitive, and the nasal passage is connected to the eyes via the tear ducts. Normally this allows the lacrimal fluid (tears) to drain through the nose. But when the fluid build-up in the nose is sufficient, the flow can block the normal draining path, so that the tears that are produced have nowhere to go.

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