You will Need:
Household Ammonia
Oxygen-Based Bleach, like OxiClean
Rubber gloves
Old toothbrush
This method is less well known and should be used only for the worst deodorant stains, the ones where every other tactic fails, you turn to Oxygen-Based Bleach & Ammonia, this is so intense you’re going to need some gloves.
Mix two tablespoons of Oxygen-Based Bleach and Ammonia together, stirl well until they’re mixed thoroughly. Apply the mixture to the stain and give it a good rub with a toothbrush for 10 minutes. Allow it to sit for another 10 minutes before washing it cold water.