A sore or scratchy throat is apt to accompany the flu. Get some relief—and wash out any secretions collecting in your throat—by gargling with a saltwater solution, says Mary Ann Pane, R.N. Dissolve 1 teaspoon of salt in 1 cup of warm water. This concentration approximates the pH level of body tissues and is very soothing, she says. Use as often as needed, but do not swallow the liquid because it's very high in sodium.