Catnip

Laurie Anne Walden, DVM

Photo by Madalyn Cox

About two-thirds of cats respond to catnip. Catnip toys and catnip plants are safe for cats and can provide sensory stimulation and environmental enrichment for indoor cats.
 
Environmental enrichment means adding things to or changing an animal’s environment in ways that enhance the animal’s mental and physical well-being. An enriched environment lets animals express behaviors that are normal for their species and helps them cope with stress.
 
Environmental enrichment is used to improve the welfare of animals in zoos and shelters, and it can also help indoor cats be happier and healthier. Sensory enrichment is part of environmental enrichment, and catnip provides olfactory stimulation for cats that are attracted to it.[1]
 
What is catnip?
Catnip (Nepeta cataria) is a perennial herb in the mint family. It can be grown in pots or planted in the garden, though like other mints it tends to be invasive if it’s not confined to a container.
 
The compound in catnip that appeals to cats is nepetalactone. Nepetalactone is a volatile substance, meaning that it forms a vapor. Cats that respond to catnip are attracted to its scent, not necessarily to its taste.
 
Some other plants contain nepetalactone and similar compounds. In a study published in 2017, most cats that didn’t respond to catnip were attracted to silver vine (Actinidia polygama). About half of the cats in the study responded to Tatarian honeysuckle (Lonicera tatarica) or valerian root (Valeriana officinalis).[2]
 
How does catnip affect cats?
Cats’ reactions to catnip include sniffing and licking it, rubbing their faces in it, rolling in it, kicking it with the back feet, and drooling. The response lasts for about 5 to 15 minutes, after which the cat doesn’t respond to the plant for an hour or two.[3]
 
Cats do not become addicted to catnip.[2,3] Nepetalactone works through the body’s opioid response system, likely providing a feel-good reward to cats that interact with catnip. Nepetalactone stimulates the opioid response system by increasing the release of natural endorphins, which probably explains why nepetalactone isn’t addicting like externally administered opiates (such as morphine) can be.[3]
 
Why are cats attracted to catnip?
The catnip response is inherited. Some big cats, like leopards and jaguars (but not tigers), are also attracted to catnip.[2] Breed, sex, and neutering status do not affect cats’ sensitivity to catnip,[4] although the catnip response seems to increase as cats grow to adulthood. We don’t know why some cats but not others have catnip-sensitive genes or why other species don’t respond to catnip in the same way.
 
So why are cats sensitive to catnip at all? It would be very unusual for animals to have an innate (as opposed to learned) behavioral response that serves no biological purpose.
 
A study published in 2021 suggested that the catnip response could have evolved as a means of pest defense. This study showed that nepetalactol (a compound in silver vine similar to nepetalactone) repels mosquitoes when it’s applied to cats’ heads. The researchers observed cats’ interactions with nepetalactol samples and found that the cats showed rolling and face-rubbing behaviors only when the samples were within reach, not when the cats could smell the samples but not come in contact with them. After more tests, they concluded that the point of the catnip response is to transfer nepetalactol to the face and body to ward off mosquitoes.[3]
 
Feel free to offer catnip to your cats if they enjoy it. Don’t rely on catnip for mosquito control, though! Mosquitoes transmit heartworms and other  diseases, and catnip isn’t effective enough as a mosquito repellant to keep your cats safe.
 
References
1. Ellis SL. Environmental enrichment: practical strategies for improving feline welfare. J Feline Med Surg. 2009;11(11):901-912. doi:10.1016/j.jfms.2009.09.011
2. Bol S, Caspers J, Buckingham L, et al. Responsiveness of cats (Felidae) to silver vine (Actinidia polygama), Tatarian honeysuckle (Lonicera tatarica), valerian (Valeriana officinalis) and catnip (Nepeta cataria). BMC Vet Res. 2017;13(1):70. doi:10.1186/s12917-017-0987-6
3. Uenoyama R, Miyazaki T, Hurst JL, et al. The characteristic response of domestic cats to plant iridoids allows them to gain chemical defense against mosquitoes. Sci Adv. 2021;7(4):eabd9135. doi:10.1126/sciadv.abd9135
4. Ellis SL, Wells DL. The influence of olfactory stimulation on the behaviour of cats housed in a rescue shelter. Appl Anim Behav Sci. 2010;123:56-62. doi:10.1016/j.applanim.2009.12.011
 
Photo by Madalyn Cox on Unsplash

---