Becoming a doctor is a long and arduous process. Between taking pre-med courses, taking the MCAT, applying to medical schools, matriculating, then taking test after test after test until you take the big one (USMLE Step 1) before which you did questions all day long for weeks from a good USMLE question bank program, after which you take rotation and shelf exam after rotation and shelf exam after rotation and shelf exam, so that you can finally FINALLY graduate to become an MD.
What awaits you on the other side, newly minted Doctor? Internship, residency, and fellowship. Sure, they pay you, but it's not very much and it is at least three more years, but up to seven! D'oh!
What am I getting at? Basically this: as you progress through your medical career, at any stage of it, you always have to keep in mind *why* you are doing all this work. Why are you sacrificing your own life to save other lives? People enter medicine for many reasons: to save lives, to perform surgeries, to earn money, to earn respect, to help those less fortunate, to help only those more fortunate, to help themselves, to help others. While all of these will be true at some stage of one's career most likely, it is important to find the common thread. I believe we are all doing this not simply to perform procedures or to prescribe pills; it is not even to treat patients. Ultimately, we are all in this to help people. The real question is: which people and in what capacity.
The people within the medical system are now secondary to the system itself. In the United States, soon 1 in 5 dollars will be spent on healthcare. The essential doctor-patient relationship now has scores of ancillary industries built around it: insurance, hospitals, therapists, outpatient centers, transportation services, and the list goes on. To master the patient care settings, one does indeed need dedication and a strong medical education. However, to master the system, it seems more and more necessary for one to have other non-medical training.
What options exist for such training? At present, complementary degrees such as a JD, MBA, MPH, MHA (masters of healthcare administration), or even an MPP (masters of public policy) can help serve a physician interested in systemic change. Let's look at the JD as an example. To get into law school is easier than medical school. It is basically a numbers game with even the interviews being optional. If you have a high GPA (which you likely do since you are interested in or already attend medical school) as well as a good LSAT score, that's it: you will be accepted to some law school in the U.S. The higher the numbers, the better the school. How do you succeed at this? Simple: do well in your classes, take them seriously, get good grades. And, take the LSAT just as seriously. Take an online LSAT prep course, do practice tests over and over again, read over the LSAT practice test solution guides very carefully. Learn from your mistakes such that you are better. Don't wait until the last minute to practice for the LSAT!
Once admitted, is law school (or any of these secondary degrees) worth it? Tough call - is the MD even worth it? Ultimately it will be what you do with the second degree that matters. If you just want more letters after your name, then I suggest you consider strongly why you want letters after your name rather than ponder another degree. All education is ultimately a means to an end. The question now is: what end is meaningful to you?