A chemist walked into his shop to find a man leaning against the wall.
"What's wrong with him?" he asked his assistant, who replied, "He came in for cough medicine, but I couldn't find any. I gave him an entire bottle of laxatives."
"You stupid idiot," said the chemist. "You cannot treat a cough with any sort of laxatives."
"Of course you can," the assistant replied. "Look at him, he daren't cough now."