Requenes.com

Here you have a product, antiperspirant, that is designed to stay on through sweaty activity. It is water's natural enemy. No wonder mere soap and water are nigh powerless to remove it.

I believe there is a general need for a product designed to remove underarm deodorant. I picture something like a large Stri-Dex^TM pad, specially formulated to cut through deodorant and antiperspirant. If no generic formula can be developed, it might be necessary for companies to market pads that go with a particular deodorant.

You would use a pad or two before showering or before re-applying deodorant intraday.