I actually treated myself with the oral rehydration solution while I was having a fit of diarrhea in Madagascar one month ago. The recipe has already been mentionned above, but I would like to add that no matter how much other taste (blueberry, orange or other) you add, one teaspoon of salt in one litre of water does taste salty. While in some cases we advocate the parenteral route (IV) for rehydration, in many cases it is better to use the oral route. This especially applies in contries with few resources - and in small children, where you don't want to put in an IV until they really need it. Gargling salty water is sometimes given as an advice to help get rid of slime in the throat, and some say you should sniff it up your nose when you have sinusitis, but drinking the amount you mention seems a bit off. - unless it is really hot and you also replenish with a lot of water. When you sweat a lot, you lose a lot of salt too. But old ladies rarely sweat a lot.