The Vagisil might (and that's a big "might") give you SOME relief, but it won't cure the problem or the reason it started.
You want Miracle II Neutralizer Gel...as fast as you can get it! It WILL soothe and stop the itching and red rash that goes along with it, but not knowing from where or what your condition stems, I don't know that it will totally cure it. But I guarantee it'll bring IMMEDIATE relief. Is this a bad yeast infection? or do you know? If you know what's causing it, I'll be glad to let you know the 'bottom line' cure :)
You'll find a zillion suppliers by doing an Internet search...or it can be found on eBay, too.