The Stafford Loans come in two variaties: subsidized and unsubsidized. With the subsidized loans, the government pays off the interes while you are in school, so if you take out $8500 in subsized loans in your first year of med school, you will still only owe $8500 when you finish med school. With the unbsubsidized, however, interest accrues while you are in school, and interest will capitalize on interest that you have already accrued. You are only allowed $8500 in subsidized loans per year, and the rest have to be unsubsidized. As far as paying off the interest while in med school, I don't know of anyone who's done it. Since most people rely on loans as their only source of income in med school, you would basically have to pay off the interest by taking out more loan money, which would then add more to the principle and interest of your loan. I don't know if it is worth it. On the other hand, when you become a resident, and decide to go into deferrment or forbearance (basically, you decide not to pay off your loans until you finish residency), it's probably a good idea to pay off interest, so that you don't come out of residency owing way more than what you owed when you started (although many people would disagree with this philosophy and would use the money to invest rather than paying off interest).