I am sorry to read these sad stories about covenia. Mine is not so tragic but it breaks my heart anyway. My ten year old male cat, Charley, had a respiratory infection and I took him to the vet in February. The vet told me about covenia, extolled its virtues and said it has no side effects. I told him to go ahead with it. Charley's infection didn't clear up and he started drinking huge amounts of water and losing weight. I took him back to the same vet and he told me Charley was losing weight and drinking water because he had a sore throat. I asked the vet about diabetes and he said Charley didn't have it. Foolishly, I let the vet give Charley another shot. Charley's infection improved but he continued to lose weight and drinking a lot of water. I did everything I could to tempt him to eat, buying him all sorts of wet food, etc. My other pets were happy with the leftovers. I called another vet, who came out to my home to see Charley. His immediate diagnosis was borderline diabetes. He didn't think Charley had leukemia or cancer but he didn't want to take a blood test because Charley's health was so fragile. This vet made a good point. Why give a relatively untried antibiotic when the others work fine? He gave Charley a shot of penicillin and some oral amoxicilin. He recommended starting Charley on low doses of insulin but was willing to try him on glipizide. Charley continues to improve, he is returning to his old self. I truly believe that covenia triggered the diabetes. Like several other people have posted, it takes weeks to get out of the cat's system. Maybe Charley is improving because his body has finally got rid of it all. I hope he comes out of the diabetes. It is possible.