I heard you just wrote a chapter on catnip. I watch my cats go crazy writhing around with catnip toys and the dried leaves you can buy at the pet store. What makes them act like this, why don't I experience this euphoria myself, and can the cats O.D. on catnip?
Utahn catlover man
Dear cat lover, (me too!)
Catnip’s ability to launch cats into a euphoric frenzy is due to a molecule called nepetalactone. Cats have a receptor or docking port, if you will, for this molecule, in their noses. Whether catnip has any effect in people as well is a mystery that remains unsolved. Humans do not possess the nepetalactone receptor. While catnip excites cats, it reputedly sedates humans. According to worldwide folk wisdom, catnip relieves insomnia, calms rattled nerves, and soothes an upset stomach.
How Catnip Works
The receptor for catnip’s nepetalactone is located in a cat’s nose, which explains why cats need only smell the plant to become engrossed. Nepetalactone resembles a molecule found in male cat urine, a pheremone. When nepetalactone binds to its receptor, sensual pleasure areas in the cat brain are stimulated. As an ardent cat lover, I can, like you, testify that cats try to saturate their entire bodies with the plant, rubbing and licking it ecstatically. We can only look upon our aroused cats’ behavior with amusement and perhaps some envy, however, because we do not have a nepetalactone receptor. Catnip may, however, affect a different receptor in our own brains.
A few scientists note that nepetalactone’s structure resembles sedating molecules found in another herb, valerian. The sleep-inducing molecules in valerian (valepotriates) also have a six-sided ring fused to a five-sided ring, and it also has what is known as an ester ( a pattern in which carbon and oxygen atoms are bonded in a particular way) in the same position on the six-sided ring.
Molecules with similar structures often produce similar effects. Valerian does have a sedative effect, because its valepotriates behave mildly like prescription sleep-aides and anti-anxiety drugs called benzodiazepines (Valium, Halcion). They all enhance the action of GABA, an inhibitory brain molecule. It is a shame that no research has yet attempted to determine whether nepetalactone has a similar effect on human GABA as well, because it very well could. Is it merely a coincidence that cultures around the world have used the herb as a sedative?
In the absence of this research, and because humans lack the cat nepetalactone receptor, most scientific references state that catnip has no known physiological activity in humans. The relaxing effects of catnip tea are attributed to the warmth of the beverage and its pleasant aroma. As anyone who has taken a warm bath knows, heat helps us relax. A simple scientific study comparing the effects of catnip tea to a beverage of hot water, as a control, would help determine whether heat is the only active ingredient in catnip tea. We have yet to learn whether or not nepetalactone is a sedative, and this would provide a whole new meaning to the term “cat nap”.
Good Uses…And Not So Good
Unlike many herbs, catnip has an almost completely unblemished safety record. There is only one documented report—that of a one-year-old boy who was taken to an emergency room after eating some questionable, old, fermenting food he had discovered, in addition to what was allegedly his mother’s catnip tea. (Whether or not it was really catnip was questioned.) He “looked drugged”, but recovered quickly. Catnip’s relatively untarnished safety record allows most herbalists to unreservedly recommend a tea made from the leaves. This is either sipped to ease jangled nerves, or drunk before bedtime to ensure sleep. The tea is even given to infants to ease colic.
A frustrating aspect of science is that, once an authority pronounces an error, retracting it from popular culture becomes practically impossible. A 1969 Journal of the American Medical Association article mistakenly labeled catnip as marijuana, confusing the effects of the two plants. Despite 1,612 letters to the beleaguered editor pointing out the error, the retraction failed to sway members of the 70’s drug counterculture, who enthusiastically commenced smoking catnip. This must have been anticlimactic for them, because it does not have any effect like marijuana. There may, however, be something behind its renown as a mild sedative.
Smoking the leaves is said to cause a sore throat, but inhaling smoke from anything causes a sore throat, and neither doctors nor firefighters advise it.
About 80% of cats are attracted to catnip. This includes lions, pumas, and leopards, but not tigers. In cats (as well as people), it is nonaddicting, nontoxic, and causes no hangover. Cats generally sleep off the effects. Enterprising cats can go to great lengths to obtain the herb (I have even had a neighbor’s cat break into my home to steal the stuff), so you may want to store the leaves in an impregnable location, like a refrigerator or freezer.
Researchers from Iowa State University have recently discovered that, while catnip arouses cats, it is a big turn-off for mosquitoes and roaches. Nepetalactone was 10 times more effective at repelling mosquitoes than the commercial repellent DEET. As concern over mosquito-borne West Nile virus rises, mosquito-repelling catnip products are being tested. At a concentration of only one-hundredth the amount of DEET normally used, nepetalactone warded off roaches as well. Why these bugs don’t like catnip remains a mystery: “It might be just an irritant,” said one researcher, “or they just don’t like the smell.”
Evidence of Action
There are regrettably no published, scientific, clinical trials assessing the effects of catnip on humans.
The Bottom Line
· Catnip might calm and sedate people, but science has not yet verified this.
· A tea made from catnip is safe, with no known side effects.
· Catnip contains nepetalactone, which resembles Valium-like, sedative molecules in another herb, valerian.