This can often be really tricky to treat. It's needs a 'multipronged' approach. At FemaleGP we often make a comprehensive plan that includes monthly fluconazole (oral antifungals), topical clotrimazole (or nystatin), topical steroid cream (to treat the associated irritant skin inflammation) and even considering treatment of your partner. However, if things have been going on for a while then the biofilm (the protective lining of the vagina is often 'unhappy' and the good bugs cannot take over and repopulate. To help this, early on in the treatment a course of boric acid is recommended. And overal antifungal treatment is usually needed for 6 months
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