I would assume Richard is right about the cause of the problem. In addition to general cleansing and probiotics, I would douche and wash with a solution of colloidial silver and baking soda. Then, use your blowdryer to completely dry the area. Do this 3 times per day until the problem is gone; then go to once per day as long as you need to.
You could also use straight colloidial silver for a mini-douche (a couple of teaspoons only) and wash externally with the baking soda and water.
BTW, this is also an excellent home cure for yeast infections.
Hope it works for you. I haven't had a yeast infection since I discovered this.