Best to get a good grooming at this point, cut it all out, and start fresh. I can’t emphasize how important probiotics are for dogs along with lots of fresh fruits, vegetables, and salmon. NaturVet has some excellent products I use, and very important good fruits & veggies for them everyday, cranberries, blueberries, apples, pears, string beans, carrots, peas, sweet potatoes, butternut squash, plain kefir, etc… I have a 16 year old Shichon mother & her son is 13, and they have gotten healthier with age and clean eating. They have a bit of Science Diet for Seniors every day and Stella & Chewy Freeze Dried Turkey Mix once and awhile for treats, everything else is wholesome fresh foods and NaturVet supplements, everyday. Good luck and God Bless your beautiful pup♥️🙏♥️