Hi., I can understand your concern.
It can be due to IBS.
He can take tab bifilac 3 times a day before food for 5 days.
Take o2 twice a day after food for 5 days
Tab pan 40 twice a day before food for 5 days
Next Steps
consult with a gastrohenterologist if issue persist
Health Tips
avoid oily spicy processed and outside food items