I can not claim that it would work for you, but if it was me, I would seek out a zapper that was strong enough to kill microbes.
Additionally, I recommend drinking a lot of real cranberry juice, not the cocktails that you find on the shelves of most stores. It should not have sugars, or other sweeteners added, nor other fruit juices. Only 100 percent Cranberry. It is strong and bitter. Tastes terrible but it works. Basically, it keeps the bacteria from adhering to the urinary tract walls.