Can you ask him? That seems outrageous to charge so much more than his regular fee. It would bug me if he doubled his fee like that--it almost feels like a kind of punishment. And kind of insulting that he would make you bring a doctor's note to excuse an emergency instead of just believing you. On the other hand, I work in community mental health that serves patients on Medicaid/Medicare, and we cannot charge people for not showing up. As a result, they don't show up frequently! Every day there are at least a couple of no shows per provider.

This is a separate issue, but FWIW, I don't give my credit card number to any of my providers. They bill me and I pay by check. That doesn't change the fact of owing for a missed appointment, but at least one doesn't feel so helpless to have unauthorized charges made to the card. With a check, at least you control when you pay the bill and can wait until the end of the billing cycle, etc. Also, my providers' billing people make mistakes all the time. I don't want to pay until I see the bill in my hand and make sure it is correct. If they just went ahead and charged my card, there would be times I am paying them money that is not due to them. Also, I tend not to share my credit card number with too many merchants for identity theft precautions. A doctor does not need to have a person's credit card number on file. None of my health care providers has ever asked for a credit card number.