For oral thrush, Mayo Clinic recommends a salt water rinse of 2.5 ml table salt dissolved in 237 ml of water. Other treatments for thrush exist, including prescription options, but they are not available in mouth rinse form.
Oral thrush is an infection of the mouth with a fungus called Candida albicans. This fungus exists normally in the mouth, says Mayo Clinic, but does not cause problems unless it overgrows. This is especially common in infants, the elderly, people with suppressed immune systems, and people taking certain medications — especially antibiotics. Treatment of oral thrush depends on the patient's age and the cause of the infection.
Ask Dr. Sears lists some common treatments for oral thrush that include a prescription medication called nystatin and an over-the-counter probiotic called acidophilus. Acidophilus can be given to children by dissolving a capsule in milk or water, or it can be swallowed whole by adults. Both nystatin and acidophilus are given to infants by applying it to the infant's mouth directly. Mayo Clinic suggests several ways to reduce the likelihood of a thrush infection, including practicing good oral hygiene, limiting foods that contain sugar or yeast, and using breastfeeding pads if the infection is present in a breastfeeding infant. To reduce the likelihood of a thrush infection caused by liquid antibiotics, wash your mouth (or your child's mouth) out with water immediately after taking the medication.