Runny noses are irritating, but not serious.

However, leaky brains are, and Phoenix resident Joe Nagy discovered the difference recently after going in for treatment for what he thought was just a nagging allergy.

"This clear liquid dribbled out of my nose like tears out of your eyes. I go, 'What is this?'" he said, according to Fox News.

Nagy struggled for 18 month. He finally sought help after an embarrassing incident when the clear liquid splashed on to model airplane blueprints, the Telegraph reported.

Nagy found out the membrane surrounding his brain had a small hole in it, msnNOW.com reported.

Brain leaks are not uncommon, according to Nagy's neurosurgeon Peter Nakaji.

"You don't really think about it, but our brains are really just above our noses," Nakaji told KSAZ-TV. "This is one of the more common conditions to be missed... because so many people have runny noses."

Brain leaks can be as tiny as a bicycle tire puncture, according to Nakaji, who says that the brain can make up to 12 ounces of fresh fluid each day.

A bout of meningitis put Nagy's surgery on hold for a little while, KRMG.com reported. However, Nakaji recently plugged the hole by going up through Nagy's nose and attaching a cork-like stoppage device made from cartilage.