Do medical bills wreck your credit score if they go unpaid?

If you're paying your other bills on time, the hospital bill will not effect your credit that much. I would call hospital itself and speak to a manager and ask them to remove the account from the collection agency until you can come to a agreement. If they still call though, just call your phone co and have them put a block on the calls. If you get letters black out your name and address and write " Return to sender".