Dr. Google is my usual second opinion.
Mostly I use it to check on things like blood test results. I have one test they do where my results are always just slightly below the normal test range. But the possible causes are nothing I have, so I guess it's just my normal range.
I also check out any new drug a doctor wants me to take before I go to the pharmacy to pick it up. I've been prescribed drugs that I refused to take after reading about the possible side effects.