My DH is an MD and their website at work includes some personal interests...actually, they haven't loaded those yet, but they were supposed to. You might find something there. I would say something small, like a mug rug, a glasses case if he wears glasses, a shopping type bag for hauling books...
My hubby has a few "doc" dwarf things. This time of year you might even find a doctor tree ornament on clearance. After all, its the thought that counts. But do skip the chocolate and sweets, we get way too much of that stuff. If you have to do food, do fruit or nuts or cheese.