You have an inherited IRA, which is different from your own IRA. You have to take a required minimum distribution from the IRA within 5 years of you inheriting the account. If it is a traditional IRA, it will be taxed as income for you, which should be negligible while in school (not negligible once a resident, so it is your advantage to start now). There are no exemptions from being taxed on these distributions, but there is no penalty for taking more than the required minimum.
My recommendation - take as much as you can while a med student. Once you are a resident, your salary will be $50k, putting you in a higher tax bracket. Any distributions will be essentially taxed within the 25% bracket, vs 10-15% now. Best strategy I think would be to take up to $50k to pay off your high-interest loan now, you'll have to pay taxes on that "income" but it'll be a lower average rate than taking it when you are a resident and already paying taxes on your salary. Unfortunately you won't be able to divide it up among multiple years since it is your final year of school.
As an aside, I'm working on a short guide for med students & residents regarding finances and management of such. We have special situations given the (likely) significant increase in salary that most standard guides don't address well. If your med school was like mine, they did about 2 seconds of education regarding this, and there are a lot of people ready to prey on us. When I'm not on call so much I'll post it to the forum.