I'm very glad Bentley is feeling better.
I'm just surprised you picked Iams... there are a lot of higher quality foods that are available that are either less in protein, different protein sources, grain-free, grain-inclusive, etc. There are sooo many options.
I will just link this site for an example of one reason not to feed Iams,
IamsCruelty.com and
http://www.consumeraffairs.com/pets/iams.html but obviously let you decide what works best for you and your dog
Because I understand every dog is different and requires different things but there are so many options out there these days besides Iams. I would even recommend Purina over Iams and I never recommend Purina in general, lol. Iams has been recalled MANY times.
Just a suggestion, I hope you don't take it the wrong way! I am no vet or any expert but have done a ton of "studying" and I've pretty much come to the conclusion that every dog is different and what works for one won't work for the other. But nowadays even some of the 'lower end' kibbles beat out Iams any day and are good for sensitive tummies.