Laxative Cough Therapy
A man is working at a pharmaceutical store, and he always gets the orders wrong. His boss tells him if he screws up one more time, he is fired.
An old man walks in and orders cough syrup. He can't find any so he gives him a laxative instead. The man takes the laxative and leaves the store.
The boss comes up and asks why he gave the man a laxative in place of cough syrup. He points towards the old man who is suddenly leaning on a lightpost and says, "Look at him -- he's afraid to cough."