I had the same problem a few years back. My podiatrist gave me a simple stretch to do, twice a day for 7 minutes, and it worked very well for me. You simply stand on a step or ledge of any kind and let your heels hang down for the duration. It feels uncomfortable at  first, then you get used to it after a few times. This got me back and running immediately. No drugs.

Superusers do not speak on behalf of REI and may have received
one or more gifts or other benefits from the co-op.