Today I found out why cats like catnip.

Catnip, which is a perennial herb in the mint family, contains a chemical called “nepetalactone” that is released when catnip is crushed.  When cats get a whiff of nepetalactone, most will start rubbing themselves against it, playing around with it, sometimes eating it, and generally will act quite bizarrely.  It is thought, but not known exactly, that this chemical mimics certain feline pheromones, specifically their theoretical facial pheromones (it isn’t known whether these actually exist, but many researchers think so, which is why cats probably like to rub their faces on various things).

Once cats have been exposed to the nepetalactone for a few minutes, it loses its effect on them and they will usually no longer be interested in it for about an hour or two, at which point the chemical will start to kick in again as they breathe it in and they will once again begin acting bizarrely around it for a few minutes.

Despite the apparent drug-like effect, it isn’t thought that catnip is in any way harmful to cats, nor is it thought that it is addictive.  Most researches think that nepetalactone simply triggers something in their brains that causes them to want to rub up against this particular smell, not unlike what dogs often do when they encounter certain smells.  That being said, cats can “overdose” on catnip, which will typically result in vomiting or diarrhea.  I’ve personally seen a cat that got into a bulk bag of catnip that was about five times the size of the cat.  The poor cat was found with catnip all over itself and more or less half buried in it.  As a result of this, for whatever reason, she was mostly unresponsive, was twitching and making random noises, and had a significant amount of drool in her fur around her head and mouth.  I expect this is something like coming home to an overdosing drug addict. 🙂  Unlike a person who’s overdosed on a drug, though, once the cat was extracted from her self made catnip bed and washed off (which was much easier to do than normal given her more or less catatonic state), within about 15 minutes of that she was completely back to normal with no residual effects.

Interestingly, not all cats respond to catnip. Whatever genetic quirk that causes them to respond to nepetalactone is inherited and only about 70% of cats out there show a behaviorally difference around catnip.  Further, cats under the age of a few weeks old also are not attracted to catnip and some even show an aversion to it.

Not only are very young cats sometimes averse to catnip, but so are cockroaches, mosquitoes, flies, and termites.  In fact, nepetalactone extract has been shown to be ten times more effective at repelling mosquitoes than DEET (N-Diethyl-meta-toluamide), which is the chemical traditionally used in mosquito repellant. However, it should be noted that when put on human skin, nepetalactone’s effectiveness as a mosquito repellant decreases quite a bit, so it’s more suitable as a mosquito repellent when sprayed on clothing or the like.

If you liked this article, you might also enjoy our new popular podcast, The BrainFood Show (iTunes, Spotify, Google Play Music, Feed), as well as:

• Why are Calico Cats Almost Always Female?
• Why and How a Cat Purrs
• Domestic Cats Can Fall From Any Height With a Remarkable Survival Rate
• The Origins of Kitty-corner, Catawampus, and other Cat Words
• The Curious Tail errr, Tale of F.D.C. Willard

Bonus Facts:

• Only female mosquitoes drink blood.  They don’t need the blood for their own nourishment; rather, they need it to be able to produce eggs.  Once the female has safely acquired a “blood meal”, she will rest for a few days while her body develops the eggs from digesting the proteins and iron in the blood, producing amino acids which are used as the building blocks for the synthesis of the egg yolk proteins.
• Male and female mosquitoes alike get their own nourishment from plant nectar and other sugar sources.
• Female mosquitoes detect possible blood sources primarily by detecting emitted carbon dioxide and octenol, which are both contained in your breath and sweat, along with a variety of other compounds which are lesser known in terms of which ones most attract mosquitoes.  People who give off more of these compounds, such as people who sweat more, will be more attractive to these mosquitoes.   The mosquitoes can typically detect these compounds up to 150 feet away.
• Mosquitoes have four stages to their life cycle: egg, larva, pupa, and adult.  During the first three stages, they live entirely in water.  During the larva stage, they feed on algae and other microorganisms and must frequently bob to the surface of the water to get air.   During the pupa stage, they do not eat, but do sit at the surface and breath air through two small tubes.  At the end of the pupal stage, the mosquitoes transform into adult mosquitoes and, after crawling to a dry place to rest and dry off, leave the water.
• DEET was created in 1940s by the United States Army; they were seeking to make a bug repellent for soldiers.  It was first used as a pesticide and later used by soldiers as a repellent in 1946.  It was released for civilian use  in 1957.
•  A repellent mixture with only a 23.8% concentration of DEET will protect the wearer for about five hours;  100% concentration of DEET has been found to be effective for about 12 hours.  DEET works by confusing the mosquito’s sensors so that they can’t zero in on the location of the compounds stimulating their sensors, such as octenol.  Recent research has also shown that mosquitoes, in particular, aren’t just having their senses confused, but also intensely dislike the smell of DEET.  DEET also acts on the brains and nervous systems of insects and, in extreme cases, can cause paralysis and eventual death by asphyxiation in the insects.
• DEET also works well as a solvent and can dissolve certain plastics, spandex, leather, and works as a nail polish remover.
• Another good natural mosquito repellant besides nepetalactone from catnip is menthol from mint.  Mint leaves or mint oil containing high levels of menthol will help repel mosquitoes and can even do more than just repel them; it has been shown that mint oil can actually kill the mosquitoes.
• A person whose body is more efficient at processing cholesterol is much more attractive to mosquitoes because the byproducts of this processing appear on the surface of the skin and seem to attract them.
• Catnip isn’t just good at inducing kitty-crazy, but throughout human history it has been smoked and used in tea and other drinks, even as an alcoholic extract.  For medicinal purposes, catnip oil also works well as a mild numbing agent.
• You can learn how to extract nepetalactone from catnip at home easy enough by going here: DIY Kitty Crack
• The known record for the most kittens born to one cat is currently held by a cat named “Dusty”.  She gave birth to 420 kittens in her lifetime and even had a litter at the very old age (for a cat) of 18 years old.
• The most kittens in one litter is 14, a feat accomplished by a cat named Bluebell.  Amazingly, all 14 kittens survived, which is rare in large litters of kittens.
• The smallest adult cat on record was named Tinker Toy.  Tinker Toy as an adult cat weighed just one pound, eight ounces and measured in at just 2.75 inches tall and 7.5 inches long.
• The heaviest cat in the world was 46 pounds and named Himmy.   This cat had a waistline of 33 inches.
• The catnip plant, originally found in the Mediterranean, was brought over from Europe to North America.
• All-total there are about 13 other chemicals that will produce a similar behavioral response in cats as catnip.  The others are: actinidine from Valeriana officinalis, dihydronepetalactone, neonepetalactone, isodihydronepetalactone, epinepetalactone, boschnialactone, boschniakine, dihydroactinidiolide, actinidiolide, iridomyrmecin, mitsugashiwalactone, and onikulactone.