One day, at the pharmacy...

The pharmacist finds a man leaning against the wall.

“What’s wrong with him?” He asks his assistant.

“He came in for some cough syrup,” explains the assistant. “But I couldn’t find any, so I sold him a bottle of laxatives instead.”

“What!” The pharmacist says, horrified. “You can’t treat a cough with laxatives!”

“Of course you can,” the assistant declares. “Look at him - he’s far too scared to cough.”