Brief Answer:
Supportive care

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. Painful abdominal cramps and nausea with occasional diarrhea needs to be evaluated. It could be acute pathology like gastroenteritis AKA stomach flu or it could be food poisoning. Apart from it if its long term history then functional bowel disorders like irritable bowel syndrome may be suspected.

I would like him to take BRAT diet ( banana rice, applesauce and toast ) , green tea, yogurt with peppermint in it etc. Drink adequately and try small frequent meals. Supportive home remedies and some over the counter antivert for nausea and vomiting and imodium for diarrhea will help. If the symptoms persist or there are signs of dehydration then take him to the hospital for some rehabilitation and some work up to find out the possible cause.

I hope it helps. take good care of him and yourself and dont forget to close the discussion please.

Regards
Khan

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