Raw goats milk is great stuff, but it has to be raw and (very important) from a good, clean source. At 15 years, if it were a case of comfort over cure I would at least consider using the medication as needed but pair it with goats milk or a good probiotic (or perhaps both).
My only issue with using anything long term (especially on a young or young-ish dog) is the potential for the effectiveness of the medication to wear off and needing to go to something stronger, having it work for 4-6 months then needing something even stronger than that, etc. I’ve had that happen before, and it’s kind of a nerve wracking place to be when your dog is getting the maximum dose of something that used to be helpful at a much lower dose, and the maximum dose is no longer working.
Just my personal opinion, of course!
