Boxer Cardiomyopathy

I have an 11 year old female boxer who was recently diagnosed with boxer cardiomyopathy. She was asymptomatic to me, but the vet heard an arrhythmia and a holter monitor & echo confirmed the diagnosis. We started her on sotalol, and 6 days later she was having a reverse sneezing attack and fainted. The vet had me stop the sotalol, and over the next week her pulse rate (which is usually low to begin with) increased. I am now reluctant to try mexilitine for fear of the same reaction. She has never fainted before, although I think I have witnessed episodes where she gets a spaced-out look and is a bit drooly.

I am considering starting her on Vetri-Science Cardio Strength, because I had excellent results with their kidney formula in another dog. I am wondering about other supplements such as hawthorn? What would be the right hawthorn dosage for a 55-lb dog? I should add, she also gets Tramadol for arthritis, gluco/chondroitin, and fish oil. Would any of these supplements interact with Tramadol? Her diet is Orijen grain free, as she has always had a very high metabolism and is very skinny.

Any suggestions would be appreciated!

[Dr. Carol Osborne, DVM]

Coenzyme Q10 dosed at 50-100 IU a day is excellent for heart health and would be a valid consideration for your boxer's cardiomyopathy
Dr Carol Osborne, DVM