Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
While cats are sensitive to essential oils, breathing in the air of a scented room should not bother them. Getting directly exposed to the concentrated oils would be a different story, though. However, it is important to remember cats have much more sensitive olfactory systems than we do, and how do we know when an ambient dose that's effective also becomes unpleasant or even painful for them?
The symptoms you describe of no longer grooming and drooling may have to do with a new diffuser/fragrance if she was exposed to a high concentration of this or in the room at all times that has this, but I would also be very concerned something else is going on such as a lesions/problem in her mouth such as a tooth problem, ulceration, tumor, etc. If her symptoms do not abate now that you have unplugged the diffuser within 48 hours, then I highly recommend you have her examined by her veterinarian.
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