Drysol is the most powerful anti-p I've ever used.
It's OTC in Canada, but I'm not sure if you need a prescription or not in the States.
It may be very similar to Certain Dri, but I'm not sure or familiar with that.
To be honest, I've stopped wearing anti-p about 10 yrs ago, and find I personally sweat LESS with just deodorant. In my mind, anti-p's were like a dam...they stopped the sweat for a while, but eventually when the dam breaks - it's like a whole stream, lol.
Deodorant just evaporates it before you feel it maybe?
Then again, I workout at noon, so I'm showering 2-3 times a day anyways, lol.
But I'm not making a joke here, I'm actually being serious. If it's really that extremely bad, have you thought about putting "panty liners" or even thin maxi pads under your arms? They're made to collect liquid...
On another note, I also personally avoid anti-p's because I'm worried that the aluminum will be detrimental to my neurological health...and I have to keep those last couple of synaptic pathways I have left working, lol.
Oh yeah, and if you haven't already done so - shave your armpits .