Can milk thistle be used as a preventative supplement in cats?

Hi all, I have four cats, but one in particular that has led me to asking this question! He's healthy, but is waiting to get in to the low income vet in our area for a checkup. We're new to our new area, so none of the vets here will advise without him being a patient, and I can't get ahold of our old vet at the moment to ask, probably because they have more pressing questions, which is fair enough! • ⁠Age: just turned 9 • ⁠Sex/Neuter status: male, fixed • ⁠Breed: Domestic longhair • ⁠Body weight: 18lb (not overweight, just a large guy!)

He is a strictly indoor cat. He has no signs of illness right now, except for being very sensitive to fragrance (watery eyes, At one point, years ago would have wheezing fits, but we quickly figured out the cause- those stupid bath and body works wall plug in oil diffusers- and his symptoms stopped and the vet decided to not persue a diagnosis since he was asymptomatic by the appointment) and can become easily stressed by loud noises.

Both of my childhood cats passed from liver failure, and I've heard of several friends' losing their babies the same way. So, I'm wondering if it would be safe or even just practical in general to use milk thistle about once a week (or more often if it works better that way) to just make sure he's processing everything well and give him a little help as he's getting older, or if that could have repercussions of some kind or even just be unnecessary. And would it be a good thing to start all my cats with for a little liver support?

Sorry! That's more words than I meant to write but I've been trying to research this for an hour and I can't find anything on using it preventatively! I'm ordering his other supplements soon and wanted to ask so I can maybe avoid paying shipping twice if it is a good idea! Thanks!!