Prescribed smz tmp ds 800-160 for ecoli BV 2x day for 5 days. What can I do to prevent a yeast infection from occurring?

Preventing yeast . Replacing the "good bacteria" (lactobacilli that keep yeast under control) with yogurt or one of the probiotic drinks may help. Otc antifungal creams may also help. Otherwise, doc may rx Diflucan (fluconazole) to treat yeast overgrowth. I usually give 2 pills, one to be taken when yeast appears, second for 7-10 days later.