for severe gastro problems like: food intolerances, vomiting, reflux, dge, diahhrea (sp?) or loose stools, as well as ezcema issues, constant ear infections and common use of antibiotics, you want to give more than recomended. If you don’t see any improvemnet with the dose you are giving, i would increase it until you can see some progress (such as firmer stool as one example).
My dd is almost 2.5 years old and she takes 40-70 billions a day, depending if she is sick or not. We worked to that dose though.
good luck.