Traitement et solutés de réhydratation lors de diarrhées, gastro et vomissements

Treatment and rehydration solutions for diarrhoea, gastro and vomiting

How to rehydrate during gastro, diarrhea and vomiting?

Your doctor or pharmacist has already advised you to drink plenty of water when you have suffered from gastrointestinal illness. Indeed, the latter can cause diarrhea and vomiting, having consequences on your level of hydration. In this article we will see what gastroenteritis is and what are its causes. Then, we will present the origins and consequences on the body of diarrhea and vomiting. Finally, we will see the means to rehydrate.

What is gastroenteritis?

Gastroenteritis is a gastrointestinal infection caused by certain viruses, bacteria or parasites that cause inflammation of the lining of the intestine. Among the various forms of gastro, we distinguish viral gastroenteritis which occurs especially in winter, generally in the form of an epidemic. In general, it lasts less than 3 days and does not require drug treatment.

There is also bacterial gastro, it can be due to different bacteria such as Escherichia coli or Salmonella. In this case, antibiotic treatment is necessary.

Whatever the cause of gastro, it causes dehydration (especially if it is accompanied by vomiting), and is accentuated in people at risk such as the elderly, infants or people with a chronic illness. The incubation period is between 24 and 72 hours, that is to say that it is after this period following contact with the bacteria that the first signs of gastro appear. The first manifestation of this is acute and sudden diarrhea. We speak of diarrhea when there is an increase in the frequency of stools (more than 3 stools in 24 hours) accompanied by a change in their consistency ranging from soft to liquid. During a gastro, you can also find nausea and / or vomiting, abdominal pain, fever and sometimes blood in the stool.

Diarrhea: causes and physiological consequences

Apart from gastro, diarrhea can be caused by food intolerance (even food allergies), chronic inflammation of the intestine, hormonal disorders, excessive transit, unbalanced intestinal flora or taking medication. Indeed, diarrhea is one of the side effects of many drugs.

Normally, water is absorbed from the intestine (in the jejunum, ileum and colon) by active salt transport and osmosis. Water is also secreted towards the lumen of the intestine, there is a real balance between secretion and absorption of water allowing optimal assimilation of nutrients then drying of the stools which then become solid.

However, by different mechanisms, the water is not well absorbed and/or too secreted, there is then an excess of water in the intestine and the stools remain liquid or soft, which causes diarrhoea. Thus, during diarrhea, there is therefore a significant loss of water and electrolytes and if they last several days, this can lead to a state of dehydration if the losses are not compensated.

To avoid the aggravation of diarrhea, there are foods that are recommended and others are to be avoided.

What to eat during diarrhea:

- Avoid all foods that promote intestinal transit such as fibers that are contained in fruits and vegetables

- However, certain fruits and vegetables are recommended during diarrhea such as bananas and carrots or cooked fruits such as compotes (apple, pear, quince, etc.)

- Avoid oily and spicy foods

- Eat starchy foods (rice and white pasta, potatoes) because they have a constipating effect

- Salt the dishes slightly more. Salt helps keep water in the body as well as mineral salts

- Favor vegetable fats rather than animal ones

- Prefer lean meats such as poultry


Vomiting is the expulsion of stomach contents through the mouth. However, since water is absorbed by the intestine (located after the stomach), this can lead to dehydration because the water does not reach the body.

Gastro, food poisoning, migraine attack, digestive tract disease, alcohol abuse, meningitis, dizziness, motion sickness or carbon monoxide poisoning can be the cause of vomiting.

How to rehydrate well?

The symptoms of dehydration are important to know how to recognize because dehydration can have serious consequences on the body. Among these symptoms, there are: intense thirst, a decrease in the quantity of urine, a dry mouth and tongue, dry skin, fever, headaches or dizziness.

To have optimal hydration and avoid worsening dehydration, there are a few rules:

- Drinking about 2 liters of water a day helps prevent dehydration

- Sodas and fruit juices are prohibited

- Coffee should be avoided as it is a laxative

- Avoid alcoholic drinks

- Drink tea, herbal teas or soups

- Sparkling but degasified water because the bubbles are not good for the digestive tract. This water is rich in mineral salts essential for better rehydration

Oral rehydration salts (ORS) are composed of electrolytes (sodium, potassium, chloride, etc.) and sugar (such as glucose) and are used to prepare a solution to treat dehydration. ORS is one of the WHO essential medicines and is used in infants and young children to prevent severe dehydration during diarrhoea. Thus, ORS “ help save millions of lives around the world ” according to the WHO and reduce “ by 33% the need for intravenous solutions ” which are used in first intention in the hospital to rehydrate and consequently lead to a decrease in hospitalization of children caused by diarrhoea.

The WHO has therefore given recommendations in terms of hydration during diarrhea, especially in young children:

Main measures for treatment:

Rehydration: with oral rehydration salts (ORS) in case of moderate dehydration or in the absence of signs of dehydration. ORS is a solution of pure water, salt and sugar. Each treatment costs just a few cents. ORS is absorbed in the small intestine and compensates for water and electrolyte losses in the stool.

Rehydration: intravenously in case of severe dehydration or shock.

Zinc supplements: they reduce the duration of the diarrheal episode by 25% and the volume of stools by 30%.

● Nutrient-rich foods: the vicious cycle of malnutrition and diarrhea can be broken by continuing to give nutrient-rich foods, including breast milk, during a diarrheal episode and by providing nutritious foods, including exclusive breastfeeding breast for the first 6 months of life, to children when they are healthy.

● Consultation with a health worker, especially for the management of persistent diarrhoea, when there is blood in the stool, or if there are signs of dehydration.”

Hydratis lozenges are based on the principle of ORS. Indeed, they are composed of electrolytes (magnesium, potassium, chloride, zinc, manganese, sodium chloride) and dextrose which is a sugar.

The pellets thus allow a better absorption of water and constitute an important contribution in electrolytes.

As the elderly are among those most at risk of dehydration, there is a specific “senior” range that comes in the form of a sachet.

These pellets and sachets can thus be used to prevent dehydration in the context of gastroenteritis and/or diarrhoea.

In conclusion, gastroenteritis can cause diarrhea and/or vomiting responsible for a significant loss of water and mineral salts (also called electrolytes) which can lead to a state of dehydration. Thus, it is necessary to hydrate well in order to compensate for the losses.

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