A friend of mine told me this story about his sister,
a veterinarian, who had to visit the doctor. The doctor asked
her all the usual questions, about symptoms, how long had they
been occurring, etc., when she interrupted him:

Hey look, Im a vet–I dont need to ask my patients these kind
of questions: I can tell whats wrong just by looking. Why cant you?

The doctor nodded, looked her up and down, wrote out a prescription,
and handed it to her, with the words: There you are. Of course,
if that doesnt work, well have to have you put down.