Fluconazole 150mg orally as a single dose
OR
Clotrimazole 500mg intravaginally pessary as a single dose at night.
If there are vulval symptoms consider use of topical clotrimazole 1% or 2% cream applied 2-3 times a day in addition to an oral or intravaginal antifungal
In pregnancy and breast feeding: See Vaginal candidiasis in pregnancy