Drinking fluids isn’t sufficient for re-hydration from diarrhea, etc. You also need to rebalance your electrolytes. One of the replies to the article contains this recipe, which looks like it would do the trick.
“Here’s a recipe for a rehydration solution (homemade Gatorade) if you do get dehydrated.
2 quarts (liters) Water
5-10 Tsp. Sugar (to taste)
1 Tsp. Salt
1 Tsp. Baking Soda
1/2 Tsp. Salt Substitute (Potassium Chloride)
1 Pack unsweetened drink mix (Kool Aid) optional for flavoring”
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