A little change
The patient shook his doctor's hand in gratitude and said:"Since we are the best of friends, I would not want to insult you by offering payment. But I would like for you to know that I had mentioned you in my will.""That is very kind of you," said the doctor emotionally, and then added, "Can I see that prescription I just gave you? I'd like to make a little change..."

Bad temper problem
Patient: Doctor, you must help me. I'm under such a lot of stress, I keep losing my temper with people.

Doctor: Tell me about your problem.

Patient: I just did, didn't I, you stupid fool!!