Yes, absolutely proactive. At 71 I know I'm very fortunate to not be on any prescribed medication, although I do have digestive problems (put down to 'IBS' - the catch-all diagnosis).
Whilst the NHS is a wonderful institution, albeit on its knees, and I have enormous respect for health practitioners, GPs are not omniscient - as already said - they are 'General' practitioners, and often receive very little training in some areas. Also, the NHS is very slow to adopt new thinking in some specialities - I'm thinking of the 'Eatwell plate' for diabetics - possibly the worst diet for keeping blood sugar under control. They are just beginning to take notice of the wealth of evidence that a low-carb diet is the way to go.
10 years ago, I had a health check by my GP, who declared my cholesterol was higher than NICE dictates, and prescribed simvastatin. I duly took it, and with in a week had horrendous muscle pain. So I stopped taking it, and told him, only to be told to control with diet. Having done a lot of reading about cholesterol, I have come to the conclusion that I'm not about to drop dead from a cardiac arrest. More recently another blood test also showed high cholesterol - this time with a new GP, and once again I said I would not take statins - no problem for her.
I always ask for a print-out of blood tests, because unless any results are flagged 'Hi' or 'Low' they are considered normal, when they could be borderline top or bottom of the range. A case in point is the thyroid TSH test, which in the UK is much wider than other countries - resulting in some people having symptoms of Hypothyroidism and not being medicated. The ranges in the US are much narrower than ours.
So, yes, always be aware of prescribed medications, and do the research - don't be afraid to question whether they are appropriate for you.
I also check Mayo clinic for various conditions - they are very reliable.