The owner of this drug store walks in to find a guy leaning heavily against a wall.

The owner asks the new clerk: "What's with the guy over there by the wall?"

The new clerk responds: "Well, he came in here this morning to get something for his cough. I couldn't find the cough syrup, so I gave him an entire bottle of laxative"

The owner, wide-eyed and excited shouts: "You idiot! You can't treat a cough with a bottle of laxatives!"

The new clerk calmly responds: "Of course you can! Look at him, he's afraid to cough."