Thank you for your query
Your child definitely seems to be suffering from gastroenteritis
. That is an inflammation of the stomach and intestines. Whether it is infective or not can be told only from his blood and stool reports. But since he has no fever
and no blood or mucus in stools, he seems to have no infection (bacterial) and in that case the medication prescribed appears to be alright. Take care to keep him hydrated and it should pass off. In case he develops fever or blood or mucus in stool, get back to your doctor. He may need an antibiotic in that case.