I remember when Febreeze came out, there was a big brouhaha on that. I asked my vet. He said that since Febreeze is sprayed on the furniture fabric, then the cat sits on it, then the cat self grooms, it is "possible" for the cat to ingest some and get sick. I decided not to use it.

But I have not heard a word about Oust. So I'm just wondering if the friend was mixing up Oust and Febreeze.