Treatment of a yeast infection while on antibiotics?

This is sort of the sister question to my last question. I determined, with help from Flutherites, that the yeast infection I currently have was caused by the Penicillin I’m on.

Since I have to take the penicillin for another week, I want to find a way to not have a yeast infection for another week.

One added bonus: I’m currently in the middle of a health insurance snafu, so I’m currently not covered.

Is there anything I can get over the counter that will treat the infection without interfering with the antibiotic? I have a mysterious cream I bought in Portugal that I think it supposed to help, but if there is a higher-powered recommended one I’ll happily switch over.

Also, since I have to go prescription-less, are there homeopathic things I can do? Just eat a ton of yogurt?

Thanks a lot!