Irish Sugar Test

One day Paddy, an Irishman, goes into a chemist shop, reaches into his
pocket and
takes out a small Irish whiskey bottle and a teaspoon.
He pours some liquid onto the teaspoon and offers it to the chemist, and
says
"Could you taste this for me, please?"
The chemist takes the teaspoon, puts it in his mouth, swills the liquid
around and swallows it.
"Does that taste sweet to you?" says Paddy.
"No, not at all," says the chemist.
"Oh that's a relief," says Paddy.
"The doctor told me to come here and get my urine tested for sugar."

Thanks Ivan and Ralph