I guess I was wrong then, but I did say I would be surprised, never did say that it wasn't possible because it is. I just thought it wouldn't be efficient to get a MD (which is a very high recognition in medicine in Australia, perhaps it is just the base level for medical graduates in other countries?) and also have a career as a pilot.
So to the threat starter, if medicine is an area that interests, go for it I guess. Just be weary of the time it may take you. For instance and roughly speaking, a medicine degree will take seven years (sometimes five or six), a MD will take an additional year if you elect to do so, a PhD would take three years. This is all before you have begun your internship which is usually two years... Could be different in other countries.
IMHO, I think there would be better avenues but each to their own. Regardless, if you do decide to get a tertiary education, choose an area of study you will enjoy.