I'm sorry to hear that your cat has this. My Sunny also had this last year and I tried a few different meds before it went away. One was in a liquid form and I think it was some kind of a blood pressure medicine for people.

I kept trying to figure out what had changed to make him so stressed out. I finally figured out that he was so afraid of his new collar that this was stressing him out. He would run around because he thought that something was chasing him. He's a very high strung cat and stresses easily. He no longer wears a collar and hasn't had the problem since.

I hope that your cat will feel better soon and that you'll be able to give his meds to him. You may need to try a liquid form instead.