If you have prolonged diarrhoea the above applies. If there is no blood present, it is possible you have giardiasis. The most important ongoing treatment is rehydration. Your body will suffer very quickly if it is dehydrated. Drinking water is effective, however, it is important that you drink purified water.
Fizzy drinks are also a good source of fluid.
Alcohol is not as it will dehydrate you further because water is required to process the alcohol through your body. Rehydration sachets containing vital salt and glucose mixtures are advised as essential to replace the fluids lost from your body. You can make your own rehydration drink by mixing a pinch of salt and a spoonful of sugar in a glass of water. Try eating plain rice in addition to your rehydration regime. Otherwise wait it out.