Milk of Magnesia deodorant
This totally works!* One pump per pit and you are good to go!
Update: 1. I switched from Phillips to a version that doesn't contain bleach (sodium hypochlorite) 2. Don't use a pump, the liquid will dry up and clog the pump. On Amazon they sell empty roll on deodorant bottles that would work much better, but I've just been pouring some out a little at a time in the cup provided and using my fingers.
*as good as other natural deodorants I've tried.