I think that some doctors almost feel obliged to send you out of the surgery with some sort of prescription. If you just did as you were told, I'm sure you could end up taking a huge cocktail after a while. The last time I went to the ER to get my torn ligament checked out they seemed almost apologetic that I would not need any treatment other than pain relief. They seemed surprised when I was pleased and said that I would sort it out for myself if nothing was broken.
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