What Causes Cats to Love Catnip

I used to watch my cat frolic and cavort on and around the catnip plants that we kept in the patio, wondering why the plant had this effect and just how it felt. So, when the cat was occupied with bullying the neighborhood dogs (our cat was the king of the neighborhood, bigger than many of the dogs and twice as tough as those that outweighed him), I went into the patio and gave the plants a big whiff. When that had no effect, I tried nibbling on one of the leaves, as I had seen the cat do on several occasions, and quickly discovered that while catnip is in the mint family, it tastes like crap. I gave up on trying to achieve cheap intoxication and went to rinse my mouth out with water, followed by milk and finally settled on tomato juice, which did the trick.

Native to Europe and Asia, catnip is now a wild weed all over North America, much to the delight of our feline friends, or at least most of them. Roughly a quarter to a third of cats are not affected by catnip, but those who are always have a splendid time with the weed… for a few minutes at a time. The effect of catnip is short-lived, but once the cat has lost interest for a couple hours, he may return for another round of capering, rolling over the plant, pawing at it, frothing at the mouth in the most disgusting but amusing way and caterwauling uncontrollably.

The chemical responsible for this entertaining reaction is nepetalactone, a ten-carbon compound derived from isoprene, which means nothing to you unless you happened to take an organic chemistry class and happened to be one of the rare students who enjoyed it and paid attention to the professor. When a cat scratches, bites or rolls around on the catnip, nepetalactone is released into the air, inhaled and then the fun begins, at least for your cat.

Unfortunately, nepetalactone has only a very mild effect on humans, acting as a weak sedative (very weak, I assure you; after my catnip experiment, I spent the afternoon evading a bunch of bikers who, for some reason, confused me for a rival—how they could mistake a ten year-old boy for an adversarial biker is anyone’s guess—and wanted to tattoo their club logo on my forehead… or somewhere even more embarrassing), an antibacterial agent and a mild antispasmodic. It can also act as a febrifuge (don’t feel stupid; I didn’t know what it was until I looked it up, either), which is just a fancy name for an antipyretic, which is just a slightly less fancy name for something that brings down a fever.

Interestingly, nepetalactone can repel cockroaches and mosquitoes, though I haven’t had an opportunity to try this out for myself (I really need to get a cat; maybe a couple dozen of them), is poisonous to some varieties of fly and is a love potion—or pheromone—to aphids, which might explain why we always had billions of the tiny little plant suckers in the patio when I was a kid. So if you decide to plant some catnip for your cat, I strongly suggest you keep your yard well stocked with ladybugs, the aphid’s archenemy.