How to Measure ORS Accurately for Safe Rehydration

December 8, 2025 •

3 min read

According to the World Health Organization, oral rehydration therapy has been estimated to decrease the risk of death from diarrhea by up to 93%. To maximize its effectiveness and ensure safety, it is crucial to understand how to measure ORS properly for both pre-packaged salts and homemade solutions.

Quick Summary

Properly preparing oral rehydration solution is vital for treating dehydration. This guide explains precise measurement methods for commercial ORS packets and homemade recipes, detailing critical safety precautions.

Key Points

Pre-packaged ORS: Always follow the manufacturer's instructions, typically dissolving one packet in one liter of clean water.
Homemade ORS: Use 6 level teaspoons of sugar and 1/2 level teaspoon of salt per 1 liter of clean water for a basic emergency solution.
Accuracy is Vital: Incorrect measurements can be harmful, with too much salt leading to salt toxicity or hypernatremia.
Cleanliness: Use clean, safe water for preparation. Boil and cool water if unsure of its safety.
Storage: Discard any unused ORS solution after 24 hours to avoid bacterial contamination.
Administration: Give the solution in frequent, small amounts. The dose varies based on age, and additional fluids are needed to replace ongoing losses.

The Importance of Correct ORS Measurement

Oral Rehydration Solution (ORS) is a vital treatment for dehydration, particularly that caused by diarrhea. Its effectiveness relies on a precise balance of salts and sugars to enhance water absorption in the small intestine. Inaccurate measurements can be detrimental; insufficient amounts of salt and sugar reduce effectiveness, while excessive salt can cause toxicity (hypernatremia), potentially leading to serious complications like nausea, confusion, and even seizures.

Precise measurement is essential for both commercial sachets and homemade solutions. The World Health Organization (WHO) and UNICEF provide clear guidelines for ORS preparation to ensure safe and effective outcomes.

How to Measure Pre-packaged ORS

Commercial ORS comes in pre-measured powder sachets, simplifying preparation. The critical step is adding the correct volume of clean water.

Step-by-Step Instructions:

Gather Supplies: You will need one ORS sachet, one liter of clean water, a one-liter container, and a clean stirring utensil.
Wash Hands and Equipment: Ensure everything is clean to prevent contamination.
Measure Water: Accurately measure one liter of clean water, preferably using a marked container.
Mix the Powder: Empty the entire sachet into the measured water. Do not use partial packets.
Stir Thoroughly: Mix until completely dissolved.
Administer and Store: Give small, frequent sips. Cover and store in a cool place, discarding any unused solution after 24 hours due to bacterial growth risk.

How to Measure Homemade ORS

Homemade ORS is an emergency alternative when commercial packets are unavailable, but it carries a higher risk of error and is only recommended temporarily.

The Emergency Recipe (WHO Standard):

Ingredients: 1 liter of safe water, 6 level teaspoons of sugar, and 1/2 level teaspoon of salt.
Method: Dissolve the sugar and salt completely. Use level teaspoons to avoid dangerous concentrations.

Key Considerations for Homemade ORS:

Use Proper Measuring Spoons: Avoid household silverware; use standardized measuring spoons. Slight over-dilution is safer than over-concentration.
Use Clean Water: If water quality is questionable, boil and cool it first.
Do Not Add Anything Else: Other ingredients can alter effectiveness.

Comparison Table: Pre-packaged vs. Homemade ORS


Feature	Pre-packaged ORS	Homemade ORS	Potential Risks	Effectiveness	Ease of Use
Measurement Accuracy	Very High	Variable; depends on user's care and tools.	Over-concentration can lead to salt toxicity (hypernatremia).	High, based on WHO's reduced-osmolarity formula.	Very Easy; just add one packet to one liter of water.
Composition	Precisely balanced salts (sodium, potassium, citrate) and glucose.	Basic salt (sodium chloride) and sugar (sucrose) ratio.	Excess sugar can worsen diarrhea; excess salt is toxic.	Good for prevention and mild cases, but less complete than commercial options.	Medium; requires careful, level measurements with proper tools.
Access & Availability	Widely available in pharmacies and health centers in most countries.	Can be made anywhere with basic household supplies.	May not be available everywhere, especially in remote areas.	Can be made in emergencies when commercial packets are inaccessible.	Can be delayed by access to water and ingredients.
Primary Use	Prevention and treatment of dehydration caused by illness.	Emergency prevention of dehydration until commercial ORS or medical help is available.	Overly diluted solutions can be ineffective.	Safe for all ages when used correctly.	Requires more vigilance to ensure safe preparation.

How to Measure ORS for Administration

Beyond preparing the solution, measuring the amount given based on age and dehydration level is crucial. Recommended amounts vary:

Children under 2 years: 50–100 mL after each loose stool.
Children 2 to 9 years: 100–200 mL after each loose stool.
Persons 10 years or older: As much as desired, up to approximately 2 liters per day.

Administer the solution slowly and frequently. For infants, use a spoon or syringe for small amounts every one to two minutes. If vomiting occurs, wait about 10 minutes and then resume giving the solution more slowly. Continue giving ORS to replace ongoing fluid losses.

Conclusion

Accurate measurement of Oral Rehydration Solution is essential for its safe and effective use in managing dehydration. Whether using pre-packaged sachets or preparing a homemade solution in an emergency, adhering to precise measurements is critical. Commercial packets should be dissolved entirely in one liter of clean water. Homemade solutions require six level teaspoons of sugar and half a level teaspoon of salt per liter of water as a temporary measure. Always use clean water and appropriate measuring tools to prevent harm and ensure optimal rehydration. For official recommendations, consult the World Health Organization.

Frequently Asked Questions

For an emergency homemade ORS, the World Health Organization recommends mixing six level teaspoons of sugar and half a level teaspoon of salt in one liter of clean, safe drinking water.

For pre-packaged ORS, you must dissolve the entire contents of a single sachet in the specific amount of water indicated on the packet, which is typically one liter.

No, you should not use a regular spoon. Household spoons vary in size significantly. Only use standardized measuring spoons to ensure the correct, safe concentration of ingredients, especially for homemade ORS.

Adding too much salt to an ORS solution can cause salt toxicity, also known as hypernatremia. Symptoms include nausea, headache, confusion, and in severe cases, seizures. This can be fatal.

Any mixed ORS solution should be covered and used within 24 hours. After this period, it should be discarded due to the risk of bacterial contamination.

No, ORS should only be mixed with clean water. Adding fruit juice, milk, or other sugary drinks can alter the necessary osmolarity of the solution, making it less effective and potentially worsening diarrhea.

If vomiting occurs, wait 5 to 10 minutes, and then continue giving the ORS solution, but more slowly. Giving small, frequent sips can help manage vomiting.

Adults should drink as much ORS as they want, as frequently as needed, to replace fluid losses. This can be up to 2-4 liters over a 24-hour period, or approximately 200 mL per loose stool.