Diagnosing?
My wife is a pharmacist and a darned good one, but she is no doctor and can only suggest medicines to treat symptoms.
For basics I have no problem. I had a Pharmacy student for a housemate in college. Brilliant guy.
They are basically doctors with a chemistry degree.
For a lot of things I self-diagnose anyway. I don’t go to the doctor frequently but when I’m sick, I often know what I have and what I need to kill it off.
It would be very convenient to go to the pharmacy, cough a couple times, let them ask the symptoms and prescribe the proper anti-biotic.
I generally get a whopper case of bronchitis annually and going to the doctor is a real pain just to get the same pills every time.
If the first treatment regimen doesn’t work, then go in to the doc.