I am Dr. Arun and will be helping you today.
I am sorry that your question was unanswered for long.
His symptoms are suggestive of intestinal infection. He may need a course of antibiotics like Metrogyl. The initial management is as following;
2) Lomotil; may only be given if the diarrhea is present.
3) Gatorade / Pedialyte
4) Plenty of fluids
5) BRAT diet; banana, rice, applesauce, toast. Vegetable broths / vegetable soups, coconut water also can help.
The primary aim is prevention of dehydration and electrolyte imbalance. If the vomiting loss of fluids is too much he is unable to drink liquids at all or vomiting everything; he may need antibiotics and / or intravenous fluids. In that case he may need to got to ER again.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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