It is always questionable whether you should pay to repair yourself in any of the MMO text-based iPhone RPG or not. This is usually because it is very expensive and often you have to use a banking system that costs a deposit fee as well. You do not have to use any kind of bank in Mafia Wars, so you may think that this would make it more economic. This is an incorrect assumption.
In reality, using The Doctor in Mafia Wars is possibly the most expensive out of all of the hospital healing features in all of the MMO text-based iPhone RPG titles. The cost is almost always so unreasonable that you would never want to use it. Your Mafia Wars character will heal on its own and you do not have to pay The Doctor. The only time that you should use the Mafia Wars Doctor is when money is no longer an issue and you want to complete a number of fights in a row. This is only beneficial if you have a large pool of Stamina in your Mafia Wars account.