This drug is an NSAID and used for inflammatory problems.
Some of the posters here (including me) also use aspirin sometimes with success. Both aspirin and naproxyn taken orally can lead to bleeding in the GI tract. And sometimes there is no warning of this, and it is silent. My neighbor had this happen and almost died from it.
more about this risk here:
http://americannutritionassociation..../deadly-nsaids

So in the short run they are helpful, but the risk of a serious side effect remains for everyone.

There is a topical patch over the counter called Salonpas.
I use these too, and avoid systemic side effects which over time Naprosyn (naproxen) can cause. Sometimes I use the OTC gelcap Aleve which I buy when on sale at Costco. I find the gelcap
very fast in onset at 220mg only and long lasting. Something about the gelcap delivery system allows for lower dose for me and sometimes just one a day is enough.

There are many mechanical causes of pain in the feet. Some are tendonitis, some arthritis, and some are nerve. It can be difficult separating these out, and I have all of them.