Chloride

Question:
I have a 2 year old Springer Spaniel with epilepsy. She has just been put on potassium bromide because she was poorly controlled by other meds. I started to transition her from a lamb and rice formula to Epigen 60, but I was told too late to be careful with switching diets while on bromide because that can affect absorption of the drug. My vet told me to look for the amount of chloride in my new food because chloride and bromide compete for absorption. Is there a way for me to find out the amount of that ingredient?

Also, for how long can I feed just Epigen 60 before incorporating something else? I saw on your site that Epigen should be part of a rotation, but I may not want to rotate often if there is an issue with affecting my dog's meds.

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