Doctor prescribed diflucan, but doesn't think i have a yeast infection (vaginitis) + back, flank pain. safe to use when i have an extra heartbeat?

Safe, but needed?: Something doesn't compute. Fluconazole (Diflucan) is only effective against yeast and would have no effect on any other kind of vaginitis. Also, vaginitis plus back and flank pain is worrisome for potentially serious non-yeast infections. Having said all that, fluconazole shouldn't cause any problem with cardiac arrhythmia ("extra heartbeat"). Discuss with your doctor!