Meds at one point were prescribed not by people but by weight. An obsese person may need more. I know dogs are given aspirin based on body weight.
Aspirin is an NSAID (Non-steroidal anti-inflammatory drug, examples are aspirin, ibuprofen (Advil), orudis and naproxen (Aleve)
It isnt too good an idea to combine NSAIDS, unless your doctor does. If I have a rough gym work out I have always taken 3 (325mg X 3) or 975mg and it works beautiful. But I have no stomach issues at all.
I reckon if you did that’d be rough on your stomach.
Many OTC (over the counter) meds do combine asprin and acetaminophen (Tylenol). The most usual combination is 500mg of each one.