Since the electrolyte-replacing formulas commercially available contain corn, having a stomach virus is made even more difficult for those allergic to corn.
When dehydrated, you need to drink something with a good balance of minerals, sugar and salts. Drink in small, frequent sips--not more than a teaspoon or so every few minutes until vomiting subsides.
This is what I made recently when I had a stomach virus with diarrhea and vomiting. It was much easier on the stomach and made me feel better than plain water or diluted fruit juice.
1 cup warm water (boiled and cooled)
1 tablespoon molasses
1 tablespoon orange juice
1/8 teaspoon salt
Small pinch of baking soda (1/16 teaspoon or less)
I used Grandma's molasses, which is corn-free. You can also use sugar if you don't have molasses, but do not use an artificial sugar substitute as this will make matters worse instead of helping. Molasses is high in many minerals and should be better than sugar to replace electrolytes.
Florida's Natural unenriched orange juice is corn-free. The enriched can contain corn derivatives in the added vitamins.
Here are a couple more recipes to choose from:
World Health Organization recipe:
1. Table Salt - 3/4 teaspoon
2. Baking Powder - 1 teaspoon
3. Sugar -4 tablespoons
4. Orange juice - 1 cup
5. Water - 1 quart/liter (4 cups)
Homemade Pedialyte (shared by a member of the Avoiding Corn Delphi forum--thank you!)
1/4 tsp salt
1 Tbsp sugar
1 pint (2 cups) water