A recent study in the New England Journal of Medicine found that women prone to vaginal yeast infections may get long-term relief from a weekly dose of fluconazole, an antifungal drug sold as Diflucan. Lead researcher Jack Sobel, chief of the Division of Infectious Disease at Wayne State University School of Medicine, says he hopes insurers will now cover preventive use; until now they've only paid for Diflucan prescribed for treatment.