You can gargle with salt water or peroxide and water. It will help some, but it will only treat the area temporarily. There really isn't a way to kill yeast, and it is naturally occurring in our bodies, so I guess we don't want to.
Other ideas, brush your tongue when you do your teeth. I usually spend more time on my tongue than my teeth, actually. Even when it's not white, the yeast is still there.
I have clear blisters and they are all the way down the back of my throat. You know if the yeast starts in the gut and it is also in the mouth, it is everywhere in between.
Once you've had a yeast infection of any kind, it is my firm belief that when you treat it, the yeast leaves the area you treat and moves to another area. I can't prove it, but having been fighting this battle for over 30 years, I'm pretty sure I'm right on this.
If you can get a doctor, more than likely an alternative dr., to prescribe pure nystatin, in powder form, you will find some relief. I took it for years, and then thought I was ok enough to stop, but I wasn't and I wish I'd never let that prescription lapse. Now I have to basically start over.
If you can't, caprylic acid is pretty good, but much, much slower working. The nystatin works on contact, but the caprylic acid has to build up in your system (like any nutritional supplement).
BTW, I had yeast so bad in the beginning (well, when I first realized what it was) that I was thought to have had aids, too. Scared me half to death. They did the test on Friday, that was the longest weekend of my life.
This crazy little fungi can reek absolute havoc on a human!! Best of luck to you in finding some relief.