Hello - welcome to the AADF forum. First of all, I have to say that I have no personal knowledge of Iams food, never having used it with my dogs. I have therefore had a look in our Dog Food Directory for the composition - see here
. It scores 1.9 and looking at the formula one can see why. The first product on the list is maize
- it should be a named meat source. It also contains wheat. There are six red ingredients.
Your dog seems to be having problems digesting some of these products so I would advise that you change the food. There is a thread here
that explains the principles of selecting a good dog food. Have a good read of it and you will know what to look out for - at the very least, read the label/ingredients list and meat should be at the top - the more meat, the better the quality. You should be able to read and understand it. The other thing is that if you see meat or vegetable derivatives, best to put the bag back on the shelf because you do not know what that consists of.
A short while ago someone also had a problem with their dog having wind and that thread is here
. There may be something in there that will help you.
Wagg Sensitive is in the same category as Iams - see here
. It is possible that if you selected a good, perhaps grain free product with no red ingredients you could feed them both the same food which might be more economical for you. Also, a better product with higher protein can often be given at lower quantities.
If you are minded to change food and need any help with this or with using the Dog Food Directory, please post back. Also, if you do change food, please let us know how you get on with it.