Salt water. Gargling with salt water to ease sore throats and coughs is something that mothers have known for generations. It turns out that this is an effective home remedy. The salt in the water can help to draw fluid out of the tissues in the throat. This can help to reduce swelling and wash out any mucus that may be sitting in the back of the throat. Try stirring ½ teaspoon of salt in warm water, cool slightly and then gargle to decrease a cough. This can be done several times a day.