My bottle of generic tablets contains 100 tablets of 220 mg Naproxen sodium. It cost about $7.
So what I see is:
60 X 500 = 30,000 mg/$35 or 857 mg/dollar.
100X220 = 22,000/$7 or 3143 mg/dollar.
Obviously the OTC med is a bigger bargain in terms of total amount of med. But there are other factors. One is that the prescription pills are much larger than the OTC pills, and the bottle correspondingly about three or four times as large. What else is in these pills? What is the difference? I don't know. I wish I had thought to ask at the pharmacy yesterday. If I think of it I will go in and ask today.