The World Health Organization (WHO) now recommends use of oral rehydration salt (ORS) solutions with an osmolarity less than that with the previous standard solution. This can be used to prevent dehydration from diarrhea of any etiology. Use of this and similar fluids can save the lives of many children, especially in developing countries.

Components of reduced osmolarity rehydration solution:

(1) sodium chloride

(2) glucose

(3) potassium chloride

(4) trisodium citrate, dihydrate



Molecular Weight

grams per liter

Molar Solution

sodium chloride

58.44 grams


44.5 mmol/L

glucose, anhydrous

180.2 grams


74.9 mmol/L

potassium chloride

74.55 grams


20 mmol/L

trisodium citrate, dihydrate



9.86 mmol/L


total sodium = 44.5 + (3 * 9.86) = 74 mmol/L

total chloride = 44.5 + 20 = 64.5 mmol/L


total osmolarity = 245 mOsm per kg water


Formula for home-made ORS:

(1) 1 level teaspoon salt

(2) 8 level teaspoons sugar (can use molasses

(3) 1 liter (5 tea cups of 200 mL or 6.6 ounces) of either (a) clean drinking or (b) boiled water that has been allowed to cool

(4) if available, 0.5 cup orange juice or some mashed banana to provide potassium (and improve the taste)


Instructions for preparation:

(1) The preparer should wash her or his hands with soap and water prior to making up the solutions.

(2) The sugar and salts should be well-dissolved before administration.

(3) Solution should be discarded after 24 hours and new solution prepared (if no refrigeration is available).


Amount to give:

(1) Adults and large children need 3 liters or more of ORS per day until well.

(2) Infants and small children should be given solution after every loose bowel movement and as needed, in small amounts frequently.

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