The common cause of loose stools in this age group is virus.
There are no safe medicines to stop the loose stools immediately.
We have to take care that dehydration
does not happen.
Continue with the medications prescribed.
you may give syrup Ondensteron (2 mg/ 5 ml) 2.5 ml thrice a day for about 2 days.
Give him plenty of fluids- water, ORS
, porridge, vegetable soups, rice based food, banana, mashed potato etc. Curd in plenty is very good for loose stools.
He must pass urine atleast 4 to 5 times in a day.
He will be okay in about 3 to 4 days.
How ever if he continues to be tired/ does not drink well/ passes urine less frequently/ very cranky please do visit your doctor again- as these suggest that he is dehydrated and might need to be hospitalized.
Hope my answer helps you.
Wish your son a speedy recovery.