I use it, diluted, on my daughter's pug, about once a week.
If you want to be extra safe, just use vinegar/water solution. I use the vinegar solution twice a week.
I also use vinegar and water in a spray bottle as a leave-in rinse before towel drying (twice a week bath). Vinegar is a wonderful chemical. It disinfects, it resets the pH, and it is an astringent which helps dry her out, which discourages fungal growth.
That dog has gone from being a smelly, oozy, nasty little beast who would scratch herself to bleeding to being a luxuriously fluffy, clean dog in two months of Jeff Chandler dog therapy. People actually like to pet her now, her ears are clean and no longer stink, and she hardly itches at all.
We have a mobile groomer who comes here once a month and grooms my three, but when we did it I always rinsed them with apple cider vinegar. Our’s seldom get the ear problems, but in the summer when they are in the water a lot we use the Vinegar recipe on the Zim Cocker site once a week after we come off the lake. It has vinegar, alcohol, boric acid and betadine in it.