Cats stopped liking catnip?!

I know some cats lack the gene that makes them enjoy catnip. This isn’t about that, unless there’s some CRISPR going on at my sister’s house.

She has two rescue cats, a brother and sister, a few years old. She’s had them about 18 months and they’re still very shy; the female will accept a few pets, the male not at all still. My sister has had cats her whole life, usually two at a time, is careful about nutrition, vet, etc.

I sent her a Christmas package that included some catnip, and she thanked me but reported:
I’m sorry to report that they seem to have sworn off catnip. They haven’t touched your most recent gift or the stuff that you sent some time ago (that I think was grown in Alberta). Perhaps they have confused Advent with Lent? dunno

Some Googling didn’t find anything useful: lots of articles about how not all cats are into catnip, and a few suggesting some health issue, typically in older cats. Since it’s both of hers, and they both used to enjoy it, this seems unlikely.

It’s not a crisis–heck, it’ll save me sending her stuff–but I’m curious as to whether anyone else has observed this, and whether anyone knows why it might happen!

Just a WAG, but maybe something caused them to both lose their sense of smell…? I believe cats can get Covid, though I don’t know if it affects their sense of smell in the same way that it does humans.

Yes, twin brothers who were batty for the stuff - I had to offer separate piles, one foot apart, to preserve the peace. Since one brother died, the other has lost almost all interest; perhaps it was competitive?
I’ve tried Spike on several different brands, but interest just won’t re-ignite. I keep hoping I’ll stumble across THE brand. By the way, I tried growing my own, but no dice; I’ll try again this spring, and try harvesting earlier.


Nice guess, but this predates covid. Thanks.


The problem could relate to the freshness and/or nepetalactone content of the catnip.

I have five outdoor cats of various ages, all over 8 years.

I grow five or so 18 inch diameter catnip plants in my front garden bed. During a typical spring all my cats will regularly roll and play in the live plants. My observations suggest a cat needs a catalyst (no pun intended) to really get into it. For me that means crushing some leaves, rubbing it on their nose or face whiskers, and picking them up and placing them in a plant.

From late summer to early spring none of my cats react to the plants or the crushed leaves. I assume the leaf oil content goes down.

I smoke a lot of weed. Over time my tolerance goes up so much that it stops really affecting me and I have to stop smoking for a couple of weeks.

Our cats get homegrown catnip flowers until they stop enjoying it. I stop giving it to them for a while and then suddenly it’s the greatest thing ever again.

I don’t know for sure if it’s a tolerance thing for cats but I do highly suspect it.

Maybe your cat realized it had a problem, and is in recovery.

GMTA – I asked her if they really didn’t like it, or if this was an intervention on her part!

All good suggestions, thanks. I don’t think the previous batch was stale–it was (supposedly) premium stuff from and even Canada Post take that long (nor did it). What I sent now was a cheapo Christmas stocking with a little vial of 'nip, which quite possibly was old.

I doubt they’ve overdosed: she’s quite ascetic and is far more likely to be cutting them off than letting them go wild.

I had also thought about COVID, but again, seems unlikely: she’s in her 60s, lives alone, didn’t go out much before and certainly doesn’t now. And the stuff from Alberta was months ago: if they’d lost their sense of smell, I’m pretty sure she would have noticed that by now in behavior/eating changes.

So any of the suggestions so far as possible, but none result in an “Aha!” moment yet.