Pain in stomach as complained by your son after finishing his course of medication can be due to the increased production of gastric acid
It can be attributed to the side effect of the medications like omnacortil
which increases gastric acid in stomach.
Junior lanzol15 is chemically Lansoprazole
, a proton-pump inhibitor
(PPI) which prevents the stomach from producing gastric acid.
So, the medication prescribed by his Doctor is correct, please continue as advised.
Meanwhile, maintain adequate hydration & give him soft diet.
Wish your son a good health & speedy recovery.
Thanks & take care.