Monistat (miconazole) cream is an antifungal agent that kills the fungus (yeast) by weakening their cell membrane in addition to its antiparasitic properties. Apply carefully into the vagina at bedtime and wash your hands immediately and avoid contact with eyes, if you miss a dose use it as soon as you remember. Monistat is not useful for itching caused by other conditions so it should be diagnosed first by a doctor prior to use. Avoid vaginal sexual intercourse, douches, tampons, spermicides, or vaginal products while on Monistat. You can stop using Monistat if your symptoms do not improve within 3 days, or if they last more than 7 days.