Tag Archives: catnip

Felines’ love for catnip could be a chemical defense against mosquitoes

Credit: Flickr.

A whiff of catnip can send cats into a frenzy but it can also make mosquitoes buzz off. The plant’s active ingredient, nepetalactone, is a super effective natural insect repellent and scientists have only recently found out how catnip keeps insect pests at bay while at the same time driving felines of all shapes and sizes completely nuts.

Catnip (Nepeta cataria) is a minty, lemony herb originally from Europe and Asia, although you can also find it growing in the Americas, particularly along roads and highways. Felines, from domestic house cats to lions, exhibit an intoxicated response when sniffing catnip characterized by licking and chewing the plants, as well as face and head rubbing against the plants and rolling over on the ground. There are no pathophysiological effects though — catnip is completely harmless to cats.

That’s common knowledge for any cat owner. What may be news to you is that catnip has a long history of use both as herbal medicine and as a powerful insect repellent in Asia, particularly in China and Japan. In fact, studies suggest that catnip compounds could be just as effective, if not more, at warding off mosquitoes as DEET, the most widely used synthetic insect repellent. Same plant, two completely different effects.

This disparity can be attributed to a class of structurally related iridoids, in particular to two isomers of nepetalactone. A study from March 2021 by researchers at Northwestern University found that the insect repellent effect is owed to interactions with a pain and itch receptor called TRPA1.

Humans, along with most mammals, also have TRPA1 receptors but the plant has no effect on us.

“We discovered that catnip and its active ingredient nepetalactone activate the irritant receptor TRPA1, an ancient pain receptor found in animals as diverse as flatworms, fruit flies and humans,” said Marco Gallio, an associate professor of neurobiology at Northwestern. “We now think catnip is so aversive to so many insect species because it activates this widespread irritant receptor. What is particularly interesting is that, unlike wasabi or garlic compounds that also activate these receptors in humans, catnip appears to selectively activate the insect receptor. This explains why humans are indifferent to it, and provides a serious advantage for its use as a repellent.”

Plants like catnip and silver vine (Actinidia polygama) likely evolved to make a chemical that activates TRPA1 as a defense mechanism. Catnip’s ancestors weren’t worried by mosquitoes or fruit flies, but they are now all repelled due to the blanket effects against insects, plant-nibbling or not, of the catnip compounds.

These findings suggest that catnip compounds could be used as a great, natural insect repellent. We could take some cues from cats, which wisened up to this millennia ago. Also in a 2021 study, researchers in Japan found that the feline automatic response to nepetalactone is owed to activation of the μ-opioid system, which is known to regulate euphoric and rewarding effects in humans.

The Japanese researchers go on to add that the characteristic, adorable-looking response that cats have to catnip suggests an important adaptive function for cats. According to the researchers, the rubbing and rolling against the plants transfers nepetalactone onto the fur for chemical defense against mosquitoes and possibly against other biting arthropods. The fact that so many species of wild big cats share the same response supports this evolutionary hypothesis.

“As a consequence, this reduces the number of A. albopictus mosquitoes that land on the animal’s head, helping to protect from mosquito bites. These findings provide new insight into this well-known and characteristic plant-induced feline response, for which the biological function was first questioned in popular science culture more than 300 years ago,” the scientists wrote in the journal Science Advances.

While catnip doesn’t make humans high, we could learn a thing or two from feline herbal medicine, especially in those tormenting summer nights at the height of mosquito season. I know I’m stocking up on catnip spray on my next camping trip.

What is catnip why do felines go crazy over it

Credit: Flickr, Richard.

Even the laziest feline couch potato can go into overdrive with a single whiff of catnip. Virtually all felines, from the adorable domestic cat to tigers and panthers go crazy over the fragrant herb (don’t believe me? Watch the embedded video below). And, you might be surprised to learn that catnip also works on humans — it’s just that it has soothing, almost sedative effects on us.

But why do cats, big or small, seem to adore catnip?

What is catnip anyway?

Catnip (Neparia cataria) is a minty, lemony herb originally from Europe and Asia, although you can also find it growing in the Americas as well, particularly along roads and highways.

It’s one of about 250 species of plants in the mint family, with a leafy green appearance. But out of all these hundreds of minty varieties, felines seem to go crazy only for catnip. In fact, the herb has long been associated with cats. Even the scientific name of the plant, ‘cataria‘, means “of a cat” in Latin.

What are the effects of catnip?

Credit: Wikimedia Commons.

You might have noticed that not all cats respond in the same way to catnip. Some go berzerk just by inhaling a few odor molecules of nepetalactone, the essential oil found in catnip, while others act totally disinterested.

It seems that only 70% of cats have a reaction to catnip, a sensitivity that is hereditary. What’s more, this sensitivity to catnip only emerges after a cat is at least three to six months old. So, your kitten shouldn’t respond to catnip at all.

Housecats that are sensitive to catnip will typically react by rolling, flipping, rubbing on the floor, and basically any object in their vicinity, especially if these objects are laced with catnip oils.

According to veterinarians, the nepetalactone binds to receptors found inside the cat’s nose, stimulating sensory neurons and altering activity in several key areas of the brain. These include the olfactory bulb (where smell is processed), the amygdala (where strong emotions such fear or pleasure are processed), and the hypothalamus (which regulates automated functions).

Some believe that the essential oils found in catnip mimic the effects of pheromones. But regardless of the neural mechanisms involved, one thing’s for sure: some cats love catnip to death!

In fact, one could argue that catnip is the only recreational drug that humans routinely give to animals.

Although catnip might look like cocaine or some other hard drug, the truth is that a feline’s frenzied reaction to the minty shrub isn’t actually chaotic and uncontrollable but rather very predictable and definite.

Credit: Pixabay.

Cats on catnip will pretty much behave the same way every time: they’ll start rubbing their faces and rolling their bodies on the surface laced with catnip simply because the high compels them to do so. After an initial phase of euphoria, about half an hour later cats will typically calm down and look a bit buzzed.

The dose of catnip and how your cat consumes it will result in different responses. Typically, the more your cat eats or inhales it, the stronger the effect.

As stated earlier, not all cats respond to catnip, but those that do don’t seem to be negatively affected in any way, nor do they develop tolerance over time to the nepetalactone and other oils found in catnip.

Do humans get high on catnip too?

Which cat owner hasn’t tried taking a big whiff out of their feline’s stash, only to be miserably disappointed. Humans do not share the same olfactory and brain machinery as cats do that allows nepetalactone to bind to receptors.

However, catnip does have an effect on people. When brewed in a tea, the minty shrub is known to produce a mild sedative effect.

Believe it or not, during the 1960s some researchers claimed that catnip could give people a marijuana-like high. But that’s just fake news. It later turned out that the researchers in question had simply mixed up the two plants.

So, no, catnip doesn’t get humans high. What’s more, if you smoke catnip or drink too much tea, it can cause headaches, vomiting, and make you feel generally sick.

Bottom line: Catnip contains volatile oils that make cats enter a frenzy when they inhale them. However, catnip is non-addictive and completely harmless. In humans, catnip is non-psychoactive and can produce a mild sedative effect in moderate doses.