I have been using this product daily now for about a year for 3 year old Cavalier King Charles Spaniel. He is happy to take it in his water bowl. Best to start of with a weak dose and gradually increase it. Not sure how effective it is as I have no idea what his mouth would be like with out it! He certainly does not suffer from bad breath or gingivitis although he does still have some tartar on his teeth. ALWAYS receive a VERY prompt delivery and much cheaper than buying in any shop.