I have a 35 pound 13 year old dog that has arthritis. She was prescribed Deramaxx a quarter of a pill once per day. I don't know what the strength of the pill is off hand and Morgan just decided to lie on my lap. I noticed improvement in Maddie's mobility right away. She hasn't held her leg up one time since she's been on it. She had a blood panel done first. But I was having that done anyway because of her age.