I mentioned in my update about our Buddy that he is taking a supplement called NAC (N-Acetyl-L-Cysteine) related to his PSOM (he also has SM and is on Gabapentin and Omeprazole). A couple people asked about the NAC and so I thought I would respond in a separate thread. I am, of course, not a veterinarian, so if you think you would like to give this a try you should definitely talk to your Vet. There are all kinds of drug interactions and other factors that need to be taken into consideration.
NAC is is a pharmaceutical drug and nutritional supplement used, in humans, for multiple purposes but primarily as a mucolytic (mucus-dissolving) agent in respiratory diseases. Lynnette Cole, DVM at the Ohio State University Veterinary School is trying it with her PSOM patients after they have had the mucus flushed from the middle ear in the hopes that it will help prevent the mucus from returning. There are no studies which have clearly demonstrated this but it is something she feels is worth trying with little to no downside. Here in the States you purchase NAC over the counter at large drugstores that sell lots of supplements or at nutrition or health food speciality stores or places like Whole Food Markets.
For those of you who might not know Dr. Cole at OSU has been conducting a study on PSOM in Cavaliers in an attempt to find a way to make the diagnosis without needing to do a CT Scan or MRI. Since she started the study she has adopted several rescue Cavaliers and is also the state coordinator for Cavalier Rescue USA (for Ohio). She was instrumental in OSU putting out a special pamphlet on Cavalier health which you can see here by clicking where it says "Cavalier King Charles Spaniel": http://www.vet.ohio-state.edu/555.htm.
Our Buddy had PSOM diagnosed, had his middle ears flushed and then two years later had to have it done again. Since the second surgery he has been on NAC. We do not know for certain that it has not returned (unfortunately still need to do a CT scan or MRI to make a diagnosis unless you see a bulging eardrum) but we are not seeing anything that makes us suspicious right now so we are keeping him on the NAC and his SM medications and watching.
Hope this is informative to some of you.