The most likely cause of the present symptoms of your husband is;
1) Electrolyte imabalnace
2) Persistent intestinal infection
He may need complete blood counts and serum electrolytes.
Meanwhile the following help him;
1) Pepto Bismol/Bismuth subsalisylate
2) Lomotil; may only be given if the diarrhea is vigorous.
3) Gatorade/Pedialyte/Electrolyte solution
4) Plenty of fluids
5) BRAT diet; banana, rice, applesauce, toast. Vegetable broths/vegetable soups, coconut water also can help.
BRATTY diet - banana, soft rice, apple sauce, toast, tea, and yogurt are recommended.
7) A tablespoon of apple cider vinegar in a glass of water twice a day.
I wish his symptoms resolve soon.
I would be happy to assist you further if you need any more information.
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