Humans can survive quite some time without food, but not without water and electrolytes. When a child is unable to eat food, drinking only water can be dangerous because it dilutes their electrolytes — this is why we prefer an electrolyte solution when eating is not possible. An electrolyte solution contains water, salt, potassium and sugar in the proper concentration. The salt and sugar also have an added benefit of helping the body absorb the water - it turns out we absorb water with a little salt and sugar much better than we do plain water.
To make sure you have the proper ratio, the easiest and safest thing to do is purchase a pre-measured product at the pharmacy (such as either Pedialyte® or Oral Rehydration Salt Packets). You can also make your own, which is actually quite simple, but it isn't quite as good because there are no readily available ingredients for potassium for a child who's not eating, and there is more potential for measuring error. I wouldn't recommend it for infants, but you can use this homemade solution in a pinch for older kids whenever you're unable to obtain a premixed solution, which I would then do as soon as possible.
Homemade electrolyte solution
Wash hands well before preparing. Be very careful with your measurements not to make mistakes. Mix the ingredients together, making sure they are well dissolved. Make fresh daily.
- 1 liter of water
- 1 level teaspoon table salt
- 1 banana (blended in) -OR- 1 cup unsweetened orange juice
- 1/2 liter coconut water
- 1/2 liter water
- 3/4 teaspoons salt.
- Pure coconut water may be used for temporary hydration needs, but because of its higher sugar content caution should be used as that may worsen diarrhea in some children.
For instructions on oral rehydration, see the dehydration and rehydration page here.