When you have diarrhea, it is very important for you to stay hydrated. Drink at least one glass of water after every trip to the toilet. If you have had significant watery diarrhea 3 times or more; if you feel weak, dizzy or have a dry mouth, you need more than just water. Rehydrate with fluids that contain both sugar and salts, such as Alvogen ORS, a special Oral Rehydration Salt. Avoid caffeinated drinks, alcohol or sugary sodas as these can make you more dehydrated.