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Did you know that when you feel thirsty, you are already dehydrated? 1,2

Drinking water is the best way to keep you hydrated throughout the day and keep the body functioning well. When excessive water and electrolytes are lost through illness, such as diarrhoea, it is critical to replace the right combination of ingredients in order for your body to absorb everything it needs to function properly. 2,3

 Normal water loss vs dehydration

Every day you experience situations which can lead to water loss.  Breathing, sweating, urinating, vomiting and diarrhoea can lead to your body losing more water and/or electrolytes than you are taking in. 1

 A healthy person’s body are made up of between 45 % and 75 % water by weight, that is roughly 42 l in a 70-kg man and about 26 l in a 50-kg woman. A newborn baby’s body consist of 75 % water, which lowers to about 60 % by 6 months. The body’s water volume is very tightly controlled, and generally fluctuates with less than 1 % per day for adults (that is 250 ml or 500 ml per day for women and men respectively). 2

When you have a fever during illness, the body heats up and needs to cool itself down by sweating. Sweat consists of water and a number of important salts (called electrolytes) like sodium, potassium and chloride. 4 Someone who has diarrhoea loses electrolytes such as sodium, chloride, potassium and bicarbonate, and can also lose up to 200 ml of fluid per kilogram of bodyweight in 24 hours – that could be more than 12 litres in one day for a person weighing 60 kg! When the loss of fluids is not adequately replaced, a person could dehydrate. 1

Recognising the signs of dehydration

How do you know if you or your child is dehydrated? In the early stages of dehydration, generally the person will experience no signs or symptoms. As dehydration increases, some symptoms may be experienced. 1

When someone shows signs of severe dehydration, it is best to get the person to a medical facility as soon as possible, as they will need to be treated intravenously (directly into the vein with a drip). 1

You may need more than water to treat dehydration due to diarrhoea

Drinking enough water during the day is very important to prevent dehydration, whether you are well or during illness such as diarrhoea. So why is drinking only plain water not enough to treat dehydration during a bout of diarrhoea? 1,2

When a person suffers from diarrhoea, the intestines are damaged or irritated and it does not absorb nutrients (specifically sodium) or water from the liquids or foods we drink or eat as they are supposed to. If sodium cannot be absorbed, the water can also not be absorbed, and dehydration can worsen. 3

So how do we get the sodium to be absorbed?

Although the intestine cannot absorb sodium because of the damage, it can still absorb glucose. As the glucose is absorbed through the intestinal wall, the sodium is also carried through with the glucose – it is called a “coupling mechanism”. Water is then drawn into the body from the intestines as water always follows sodium. 3

Oral rehydration solutions (ORS)

An oral rehydration solution (ORS) used to treat dehydration should have a specific formulation with the correct combination and quantities of ingredients to replace the salts lost in watery diarrhoea. ORS should be given to all persons with diarrhoea, no matter their age, and regardless of whether they show signs of dehydration or not. The World Health Organisation (WHO) found that dehydration from acute diarrhoea of any cause and at any age, except when dehydration is severe, can be safely and effectively treated in over 90 % of cases by the simple method of oral rehydration using a single fluid. 1,5

REHIDRAT Oral rehydration solution

REHIDRAT® is SA’s  No. 1 oral electrolyte replacement solution, contains an optimal balance of sugars, salts and minerals to replenish lost fluids and help prevent and treat dehydration and electrolyte depletion.6

REHIDRAT® is available in 3 flavours - Blackcurrant, Orange, Vanilla and contains no artificial preservatives, sweeteners or colourants and is suitable for the whole family.

Preparing REHIDRAT® is easy – follow us on YouTube for easy instructions

Offer oral rehydration solution to infants using a method that they are familiar with e.g. a baby bottle, cup or spoon. Always prepare the solution fresh every day and dispose of any solution not used after 24 hours.

Infants less than 1 year of age should be given ½ to 1 cup (100 – 200 ml) of REHIDRAT® for every bowel movement.

Children 1 to 5 years of age should be given at least one cup (200 ml) for every bowel movement, while older children and adults should drink enough REHIDRAT® to quench their thirst and replace the fluid lost in every stool.

Medical References

  1. The treatment of Diarrhoea – A manual for physicians and other senior health workers. World Health Organisation. Accessed 11 April 2020. Available at;sequence=1.
  2. Benelam B, Wyness. Hydration and health: a review. Nutrition Bulletin, 2010;35:3–25.
  3. Goodall RM. Oral Rehydration Therapy: How it Works. Accessed 8 April 2020. Available from
  4. Wedro B. Dehydration. MedicineNet [Online]. Accessed on 1 Sept 2021. Available at
  5. World Gastroenterology Organisation Global Guidelines Acute diarrhea in adults and children: a global perspective. February 2012. Available from
  6. IQVIA Data December 2020.

S0 REHIDRAT® ORANGE. Reg. No. Y/24/181.


S0 REHIDRAT® VANILLA. Reg. No. N/24/103.

Each 14 g sachet of powder contains: Sodium Chloride 0,44 g, Potassium Chloride 0,38 g, Sodium Bicarbonate 0,42 g, Glucose 4,1 g, Sucrose 8,1 g.

For full prescribing information, please refer to the Professional Information approved by the medicines regulatory authority.


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