I've been giving this to my chihuahua since she has been experiencing Cluster Seizures for the last 2 1/2 years and just recently someone said that they couldn't believe that she was 7 years old. She is outgoing and active even with her seizure medication. I also give my other dog who is 9 1/2 years old Vitality and I noticed the other day that her cataracts in her eyes are not as apparent as before. It's taken 2 bottles so it's not an overnight thing but regardless I think these mushroom tonics do really work.