Severely malnourished children can safely take standard oral rehydration
11 Mar 2026
New results from the GASTROSAM clinical trial show that the rehydration strategy commonly used in non-malnourished children is also safe for children with severe malnutrition with dehydration. These results were published yesterday in The Lancet Child and Adolescent Health.
It’s estimated that 17 million children worldwide are severely undernourished. The most extreme form – severe acute malnutrition, or SAM – is a leading cause of paediatric hospital admissions in Africa. But international guidance on rehydrating children with SAM who have severe dehydration due to gastroenteritis differs from that for children who aren’t classed as severely malnourished.
Children with SAM and dehydration are recommended to take a special rehydration solution called ReSoMal. This solution contains less sodium than the standard solution that is recommended to treat children who are not malnourished. This is due to concerns about sodium and fluid overload. However, there is not enough evidence to show that standard rehydration solutions cause those problems.
To address this question, the GASTROSAM trial tested if the standard rehydration solution was safe to treat children with SAM and dehydration. This part of the trial included 415 children hospitalised with SAM with moderate to severe dehydration caused by diarrhoea. They were randomised into one of two groups
- Oral rehydration solution (ORS)
- Lower-sodium containing ORS for malnutrition (ReSoMal)
The study was carried out in Niger, Nigeria, Uganda, and Kenya.
After 28 days, GASTROSAM found no difference in survival between the two oral rehydration strategies. Importantly, neither rehydration strategy caused fluid overload, which happens when the body has more fluid than it can handle.
These results showed that the standard oral rehydration solution is not harmful to treat children with SAM and dehydration and is no less safe than ReSoMal solution that is currently recommended by the World Health Organisation. In fact, children who had the standard rehydration solution had fewer side effects in comparison with those who had ReSoMal.
These results open the possibility of a review of existing guidance worldwide. In particular, a simplification of the recommendations supporting the use of oral rehydration solution to treat dehydration regardless of the nutritional status of the child.
Previous results from the trial showed that there was no evidence of a difference between intravenous rehydration and the oral rehydration strategy currently recommended, and intravenous rehydration was as safe as the oral strategy.
These results from GASTROSAM will be shared with global health bodies and policymakers to support evidence-based updates to clinical guidelines for managing SAM in emergency and hospital settings.
The trial was led by Imperial College London’s Institute of Global Health Innovation, in close collaboration with MRC CTU at UCL and Médecins Sans Frontières.
GASTROSAM was funded by the Joint Global Health Trials Scheme of the United Kingdom’s Medical Research Council, the UK Department for International Development and Wellcome (Grant Number MR/R018502/1) and by Médecins Sans Frontières.
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