ORT and ORS: what is the difference?

ORT is the administration of fluid by mouth to prevent or correct the dehydration that is a consequence of diarrhea. Through the ages, and in most cultures, many claims to have used various types of fluids for their children during diarrhea. In the Indian sub-continent, the use of rock salt with soft cooked rice in a thick gruel has been reported as far back as 3000 years ago. But effective and safe treatment had to wait the discovery of the scientific basis for oral therapy. Most of the trials necessary for this were conducted at CRL/ICDDR,B during the period 1964 to 1968. In 1975, based on the work performed at CRL/ICDDR, B, UNICEF and WHO agreed on a single formula oral rehydration solution, and this has become known as ORS. This formula results in safe and optimal absorption of essential electrolytes and thus rehydration. ORS consists of 4 constituents: 1. sodium chloride, 3.5 grams; 2.trisodium citrate, dihydrate, 2.9 grams; 3. potassium chloride, 1.5 grams; 4. glucose, 20,0 grams; these are to be dissolved in 1 liter of clean drinking water. ORS is generally provided pre-packaged in a dry form to be reconstituted when required.