The most simple advice, I think, is to find a good doctor. This can be hard in today's world of corporatized medicine where doctors get paid commissions by pharmaceutical corporations to push their drugs. My mom's worked in the healthcare industry as a secretary and tech for over twenty years and has noticed this trend of, for lack of a better term, doctors selling-out. Incidentally, these sell-out doctors also tend to order a lot of expensive tests that are probably unrelated to what ails you because they get a kick-back for those as well. If you're getting orders for a CAT scan for a head-cold, probably time to find a different doctor.

But there are still good doctors out there, those who don't blindly prescribe drugs and tests left and right but actually practice good medicine. They will know what to prescribe and what tests to order that are specific to your care, and offer "alternative" treatments as well ("here's a prescription for a stomach medicine, but why don't you wait a day and try some ginger or mint tea first.") I put alternative in quotes because, while they're described as such in today's big-pharma world, these weren't "alternative" even as recently as the 1970s, they were well tested options for treatment

It's always good to do some of your own research as well, and bring this up when you see your doctor. You may bring up bits of info that helps form a better diagnosis. Like a good mechanic, if you find a good doctor cling to him/her and trust that they're not trying to exploit you for more commissions.