What is the right way to prepare ORS?

November 12, 2025 •

3 min read

According to the World Health Organization (WHO), oral rehydration solution (ORS) is a simple and life-saving intervention for treating dehydration, especially from diarrhea. Understanding what is the right way to prepare ORS is crucial to ensure its effectiveness and safety, as incorrect mixing can render it ineffective or even harmful. The correct balance of glucose and electrolytes is vital for proper intestinal absorption and to replace the fluids and salts lost during illness.

Quick Summary

A direct guide detailing the correct preparation of oral rehydration solution using both pre-packaged sachets and a precise homemade recipe with salt and sugar.

Key Points

Pre-packaged ORS: Always follow the instructions on the packet precisely, mixing the entire sachet with the specified volume of clean water.
Homemade ORS: Use the WHO recipe: 1 liter clean water, 6 level teaspoons sugar, ½ level teaspoon salt. Use level measuring spoons for accuracy.
Safe Water: Use clean drinking water; if uncertain of its safety, boil it and let it cool before mixing.
Storage Limits: Prepared ORS solution must be used within 24 hours or discarded to prevent bacterial contamination.
No Extra Ingredients: Never add extra sugar, salt, milk, or juice, as this will disrupt the delicate electrolyte balance and potentially worsen the condition.
Proper Technique: Stir thoroughly until all dry ingredients are completely dissolved for a uniform and effective solution.

Oral Rehydration Solution (ORS) is a critical tool for managing dehydration caused by vomiting, diarrhea, or excessive sweating. Whether you're using a commercial sachet or preparing a solution from scratch, precision is the key to ensuring it is both safe and effective. A properly mixed ORS works by leveraging the sodium-glucose co-transport mechanism in the small intestine to maximize fluid and electrolyte absorption. Improper preparation, especially adding too much salt or sugar, can worsen the condition.

Preparing Pre-Packaged ORS Correctly

Pre-packaged ORS sachets are formulated to the exact specifications recommended by organizations like the World Health Organization (WHO) and UNICEF. For this reason, following the instructions on the packet precisely is the most reliable method.

Step-by-Step Sachet Preparation

Gather Supplies: Use a clean, sterilized container (at least 1 liter), a clean stirring utensil, and a fresh ORS sachet.
Wash Your Hands: Ensure hands are thoroughly washed with soap and clean water.
Use Safe Water: Measure the exact amount of clean drinking water specified on the packet (typically 1 liter). Boil water for at least 10 minutes and cool if its safety is uncertain.
Mix Entire Sachet: Add the full contents of the ORS powder sachet to the measured water. Do not use only a portion.
Stir Until Dissolved: Stir until all powder is completely dissolved.
Administer and Store: The solution is ready. Pour into a clean cup and administer in small sips. Cover and store any unused solution.

Making Homemade ORS (WHO Recipe)

If pre-packaged sachets are unavailable, a homemade ORS can be made using the WHO recipe. Precise measurements are critical.

Homemade ORS Ingredients and Directions

Ingredients:
- Clean Water: 1 liter. Boil and cool if necessary.
- Sugar: 6 level teaspoons.
- Salt: ½ level teaspoon.
Directions:
1. Use a clean 1-liter container.
2. Add 1 liter of safe water.
3. Add exactly 6 level teaspoons of sugar.
4. Add exactly ½ level teaspoon of salt.
5. Stir until dissolved. Use level spoons for accuracy.

Crucial Precautions and Common Mistakes

Correct preparation involves more than just mixing. Follow these precautions for effectiveness and safety.

Do Not Alter the Formula: Adding extra sugar, salt, juice, or milk is dangerous as it changes the osmolality and can worsen diarrhea. While a mashed banana can add potassium, it should only be added after the ORS is correctly prepared.
Use Proper Measurements: Accurate, level measuring spoons are vital. Avoid approximating salt with methods like a 'finger-pinch'.
Use Safe Water: Contaminated water can introduce infection and negate the benefits.

Storing Your Prepared ORS Solution

Prepared ORS has a limited shelf life due to bacterial contamination risk.

Storage Duration: Use within 24 hours and then discard.
Storage Location: Store covered at room temperature or refrigerated. Room temperature solution may be preferred to avoid stomach cramps.

Homemade vs. Commercial ORS: A Comparison


Feature	Commercial (Sachet) ORS	Homemade (WHO Recipe) ORS
Accuracy	Extremely high due to pre-measured ingredients and low-osmolarity formula.	Depends on accurate household measurements; variations can alter electrolyte balance.
Availability	Requires purchase; widely available through health organizations.	Ingredients are common household items, available in emergencies when sachets are not.
Efficacy	Optimized for maximum absorption.	Effective when mixed correctly but may be less precise than commercial options.
Convenience	Simple and quick to prepare with just water.	Requires careful, level measurement, which can be difficult in urgent situations.
Cost	Low-cost but requires purchase.	Extremely low-cost using basic ingredients.

What to Avoid When Preparing ORS

To ensure your ORS is safe and effective, avoid these critical mistakes:

Don't add extra ingredients: Avoid adding sugar, juice, soda, milk, or other flavors that are not part of the standard recipe or instructions.
Don't boil the solution: Do not boil the ORS powder once mixed with water. Use boiled and cooled water for mixing.
Don't save old solution: Discard unused ORS after 24 hours to prevent bacterial growth.
Don't approximate measurements: Use level measuring spoons for accuracy, especially for homemade ORS.
Don't use it as a regular drink: ORS is a medical treatment for dehydration, not a daily beverage.

Conclusion

Knowing what is the right way to prepare ORS is essential for managing dehydration. Whether using a commercial sachet or a homemade recipe, attention to detail in ingredients, measurements, and water quality is crucial. Commercial sachets are the most accurate and reliable option when available. For homemade ORS, strictly follow the WHO proportions of 1 liter of clean water, 6 level teaspoons of sugar, and ½ level teaspoon of salt for safety and effectiveness. Adhering to these guidelines ensures you prepare a safe and effective rehydration solution.

World Health Organization link on ORS guidelines

Frequently Asked Questions

Yes, using commercially bottled water is an acceptable and safe option for preparing ORS, provided it is clean drinking water. It eliminates the need for boiling if the local tap water's safety is a concern.

No, it is not safe to add extra sugar. The ORS formula is a precise balance of sodium and glucose. Adding more sugar can increase the concentration, potentially worsening diarrhea rather than treating it.

A prepared ORS solution should be consumed or discarded within 24 hours of mixing. After this period, the risk of bacterial contamination becomes too high.

No, you should never mix ORS with milk, juice, or other soft drinks. These liquids can alter the delicate electrolyte and sugar balance, compromising the solution's effectiveness.

If you add too much salt, the solution will have an incorrect and potentially harmful electrolyte balance. You must discard it immediately and prepare a fresh batch with precise measurements.

For children, you can try adding a few drops of lemon juice or a mashed banana to the already-prepared ORS to improve the taste, but only if directed by a healthcare professional. Some commercial ORS packets are also pre-flavored.

You can store prepared ORS in a clean, covered container in the refrigerator for up to 24 hours. However, some sources advise against drinking it cold, as it might cause cramps, so you may want to bring it to room temperature before administering.