I'm not a veterinarian. The Barn Cat Way is general information based on long experience with cats, not veterinary advice, and it doesn't replace your vet.
If your cat is sick or hurt, or you think she's eaten something harmful, call your vet or an animal poison helpline right away. Don't wait to see if she gets better.
Always follow product labels. Every cat is different, and you use the information in the manual at your own risk.