How Catnip Works and Which Cats Respond to It

Catnip works because it contains a compound called nepetalactone that, when sniffed, triggers a short burst of euphoric, playful behaviour in cats that are wired to respond. Roughly two-thirds of cats react; the rest feel nothing, and that's down to genetics, not anything you've done wrong. Kittens under three to six months usually don't respond at all.

What's actually happening

When a susceptible cat sniffs catnip, the nepetalactone binds to receptors in the nose that feed into the parts of the brain governing emotion and behaviour. The result is the familiar routine: rubbing, rolling, drooling, head-shaking and a burst of energy. It's a sensory reaction triggered by smell, not something the cat eats to feel.

The effect is short and self-limiting. Most cats are off in about ten to fifteen minutes, and then they go "nose-blind" to it for a while, usually an hour or two, before they can respond again. That cooldown is normal and there's no way to rush it.

Eating versus sniffing

It's worth knowing that sniffing and eating catnip do slightly different things. The sniff produces the lively, excitable response; eating a little tends to have a milder, more mellow, sometimes sleepy effect. Neither is harmful in the amounts a cat would normally take, and a cat that nibbles a catnip toy isn't doing itself any damage.

That said, a cat that suddenly gorges on anything, or seems genuinely unwell after, is worth a quick word with your vet rather than guesswork, since persistent vomiting or off behaviour is never just "the catnip."

Why some cats don't react

Responsiveness to catnip is inherited. A cat either has the genetic trait or doesn't, in much the way some people can smell certain scents and others can't. If your cat sniffs, shrugs and walks off, they simply aren't one of the responders, and no amount of fresher or stronger catnip will change that.

Age matters too. Very young kittens and some elderly cats show little or no reaction. So if a new kitten ignores their catnip mouse, give it a few months and try again before writing it off.

Using catnip well for indoor cats

For indoor cats especially, catnip is a handy enrichment tool when used with a light touch:

• Use it occasionally, not constantly. Cats can become temporarily desensitised with very frequent exposure, so a few times a week keeps the magic alive.
• Pair it with play. A sprinkle on a scratching post encourages use; catnip on a toy turns a quiet evening into a proper session. Browse interactive cat toys you can combine it with.
• Refresh dried catnip. It loses potency over time, so an ignored old toy may just be stale. Crushing it gently releases more scent.
• Watch over-arousal. A small minority of cats get over-stimulated and a bit nippy. If yours does, give them space until they settle and use less next time.

If catnip does nothing for your cat

Plenty of non-responders still enjoy enrichment, just through different routes. Silvervine, valerian and honeysuckle trigger a similar response in many cats who ignore catnip, and our guide to Catnip Alternatives: Silvervine, Valerian and More covers them. For a wider toy box, see Best Toys for Indoor Cats: A Buyer's Guide, and if your cat does love the stuff, Best Catnip Toys in the UK for Happy Cats rounds up the good ones.

For more on keeping a house cat busy and content, our Indoor Cat Enrichment hub ties it all together, and you'll find toys to try across our cat toy range.

The short version: catnip is a safe, harmless treat that works on most cats and does nothing for some. Use it now and then, pair it with play, and don't worry if your cat is one of the unbothered ones.