It is normal for a kitten to get diarrhea from any food change but canned food is much better for cats.
Please read article written by feline vet:
Max may be drinking a lot because dry food is very dehydrating and so is diarrhea.
Get some smooth pate canned kitten food or human baby food chicken with no onion powder.
Add one tablespoon of rice cereal or boiled white rice to each can or jar.Feed until the stool is normal for 48 hours.
In addition give him a half tsp of plain yogurt every day for good bacteria
If he gets dehydrated give him tuna water drained from the can.
Please let me know how he is doing .Reply here or we can speak on the phone.
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