cough medicine

[just.me]

The owner of this drug store walks in to find a guy leaning heavily
against a wall.
The owner asks the clerk : "What's with the guy over there by the
wall?"
The 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 clerk calmly responds: "Of course you can, look at him, he's
afraid to cough."