Here's Ace, the cat that is not supposed to be in the house. It's a long-time running joke.
Ace had bronchitis recently. He gets it every winter, and it can last a month or longer. Since it does not respond to antibiotics, we assume it is viral.
This year, I used one drop of oregano oil each day to knock it out. In 48 hours, I could tell a big difference in his breathing. On day three, all symptoms were gone, but I added two days just to be safe. Five drops of Oregano Oil = effective and economical! I put it on his paw which he found highly offensive, but he licked it off.
The first day, he had no reaction to me putting it on his paw. He was very ill though. The second day, he pulled his head back. On the third day, he meowed, jumped up, and angrily ran off to hide from me. On the fourth day, he knew the bottle and was ready to move as soon as I grabbed it!
Before you write me, I know it is all over the internet that cats can't use it. The holistic vet said it is perfectly OK in small quantities for a short duration. It did not harm Ace in the least. He got well and returned to full energy very quickly. However, I am not a vet. Use this info at your own risk.