Open a bag of catnip and one cat comes skidding round the corner, rolls on the floor, rubs her face in it and zooms off down the hallway. Another cat sniffs it once, looks at you, and walks away. Same plant, completely different reactions. The science behind that turns out to be stranger, and more useful to cats, than anyone expected.

A mint with a secret

Catnip, Nepeta cataria, is a perennial herb in the mint family. The magic is in an oil in its leaves and stems called nepetalactone. When a cat breathes it in, it acts on cells in the nose and upper airway, and the cat's body responds by releasing endorphins, its own natural feel good chemicals.

That is not just a guess. When researchers have given cats a drug that blocks the brain's opioid receptors, the rolling and rubbing stops. It is one of the clearer examples of a plant switching on a reward system in an animal's brain.

The ten minute party

The effect kicks in within seconds of a good sniff. You might see rolling, face rubbing, purring, drooling, sudden bursts of energy, or a cat who simply sits very still with a faraway look. Either way, it doesn't last long. PetMD's veterinary writers put a typical session at around ten minutes, rarely more than fifteen.

Then the switch turns off. For roughly one to two hours afterwards, most cats won't react to catnip at all, however much you wave it at them. Offer it again later and the whole show can start over.

Why some cats just don't care

If your cat ignores catnip, nothing is wrong with them. The response is inherited, so it runs in families, and somewhere between a third and a half of cats show little or no reaction, according to Humane World for Animals. Kittens are a separate case. Most don't respond at all until they are somewhere between three and six months old.

A 2017 study tested 100 cats in homes, a shelter, a sanctuary and a vet practice in Riverside, California, with four different plants. About 68 percent responded to catnip. Even more, 79 percent, responded to silver vine, a climbing plant from East Asia. Here is the useful part: of the cats who ignored catnip, about 71 percent reacted to silver vine instead. So if your cat seems immune, silver vine is worth a try.

The same study also offered the plants to some big cats. The tigers were mostly unimpressed by catnip. The bobcats liked silver vine.

The twist: it may keep mosquitoes away

For a long time, the catnip response looked like pure fun with no purpose. Then, in 2021, a research team led by Reiko Uenoyama published a study in Science Advances that changed the picture.

They focused on nepetalactol, the closely related compound that makes silver vine so irresistible. When they offered it to 25 lab cats, 30 feral cats, and even an Amur leopard, two jaguars and two Eurasian lynx, the cats spent far longer rubbing their faces and heads against it than against plain paper. Within minutes, their endorphin levels had gone up.

Then came the clever test. The rubbing spreads the plant's oils onto a cat's face, head and fur, and those oils happen to repel mosquitoes. Cats who had rubbed on silver vine had significantly fewer tiger mosquitoes land on them than cats who hadn't. The researchers suggest that the feel good reward may be exactly what keeps cats doing something that protects them from bites.

So that ridiculous face first flop into a pile of catnip might be part party, and part bug spray.

Getting the most out of it

• Keep it special. Humane World for Animals suggests offering catnip just a few times a week, so it stays exciting.
• Store it cold. Dried catnip keeps its punch longest in an airtight container in the freezer. Catnip toys lose their scent over time, so refresh them every few weeks.
• A little goes a long way. Catnip isn't addictive, and cats can't overdose on it in any dangerous way. But a cat who eats a lot of it can end up with an upset stomach.
• Know your cat. Most cats get happy and silly. A few get overexcited or grumpy, and cats who are anxious or quick to swat may be better off without it.
• Try silver vine if catnip gets a shrug.

If your cat is one of the lucky responders, a catnip spray is an easy way to wake up an old toy or make a new scratcher more tempting. We carry HuggleKats Happy Kat Nippie Catnip Spray, and you'll find plenty to spray it on in our cat toys.

This is general information about a common cat treat. If you have questions about whether catnip suits your cat, ask your vet.

Sources: Humane World for Animals, What Is Catnip?; Matthew Everett Miller, DVM, for PetMD, Does Catnip Make Cats High? (2022); Bol and colleagues, Responsiveness of cats to silver vine, Tatarian honeysuckle, valerian and catnip, BMC Veterinary Research (2017); Uenoyama and colleagues, The characteristic response of domestic cats to plant iridoids allows them to gain chemical defense against mosquitoes, Science Advances (2021); VCA Animal Hospitals, What does catnip do to cats? Photograph by zhang kaiyv on Unsplash.