Combine two parts apple cider vinegar with one part regular white vinegar in a spray bottle, shake well and apply it on the furniture your dog likes to chew. Cayenne Pepper Spray. If citrus and apple cider vinegar sprays arent working, try cayenne pepper spray. Cayenne peppers arent harmful to dogs, but be careful nevertheless since pepper spray liquids can irritate their eyes and nose, so you might not want to try it as a first option. Simply add 1 or 2 teaspoons ground cayenne pepper ...