By Carrie Hyde, The Spaw Pet Life Coach | March 20, 2023

Whether they’ve got a scrape, a burn, or a cut, our pets love to lick their wounds. Given how insistent they are on the practice, it seems counterintuitive to make them stop. I mean, certainly, there’s a reason they’ve evolved to do this.

But, if that were true, why do e-collars exist? And why do vets wrap wounds and tell us to put t-shirts on our pets to keep them from getting to their injuries?

Today, we’ll take an in-depth look at the science behind saliva and how letting your dog or cat lick their wounds can be beneficial. We’ll also look at those special circumstances when licking the wound is more likely to do more harm than good and how to make your pet stop.

The Benefits of Letting Pets Lick

Surprisingly, research has shown that dog and cat mouths are a lot cleaner than human mouths. In fact, their saliva has many properties that kill bacteria.

But having antibacterial saliva is only one reason dogs and cats lick their wounds. Licking also helps remove debris, increase blood flow to the area to speed up healing, and helps reduce pain and release calming endorphins.

Removes Debris

When you don’t have hands you have to get a little creative when it comes to cleaning out a wound that might be filled with dirt or foreign objects. And that is exactly why nature gave dogs and cats long, flexible, muscular tongues.

Their tongue literally acts like a wet rag to help remove debris from wounds.

Hair, dirt, pieces of rust, rocks, seed heads, and all types of things can get embedded in a wound when you spend your life running through fields and gardens. By removing these foreign objects with their tongue, cats and dogs assure that they do not fester in the wound and cause infections. Removing objects, even sterile or benign debris, is also important to allow the wound to heal properly.

But it’s not just visible grime that the tongue washes away. It also removes microscopic pathogens that have been introduced into the torn flesh. Like saline pumped into a cut, a dog’s tongue helps flush these bacteria and protozoan away so they can’t feed on the damaged tissue.

Saliva has Antibacterial Properties

Even if pathogens have a chance to establish in the wound, dogs and cats have a genius defense system to help heal infection: their impressive saliva.

Animal saliva contains thiocyanate and lysozyme, two detoxifying substances known to have antimicrobial properties. Both e. Coli and s. Canis, two common bacteria found in dog wounds, are neutralized by these properties of saliva(1).

Adding to the antimicrobial effect of saliva is the high concentration of nitrate found in it. This compound is constantly being turned into nitrite by facultative anaerobes present on the surface of the tongue. When this nitrite is converted to nitric oxide during wound licking, it becomes a powerful antimicrobial agent(2).

While there is some possibility of bacteria being introduced into the wound from the tongue, the antibiotic effects of licking far outweigh the potential for introducing infection.

Increases Blood Flow

Beyond saliva, the action of licking is also beneficial. The movement of the tongue over the skin stimulates blood flow which can hasten healing.

Adequate blood flow is necessary in order to bring oxygen to the wounded flesh. Not only does oxygen play a role in fighting infection, but it is also important for rebuilding tissue. Oxygen plays a critical role in the growth of new capillaries and in creating collagen(3).

Increased blood flow also helps bring white blood cells to the site of the wound. Macrophages, a specific type of white blood cell, are especially important as they play a role in protecting the wound from infection by producing a clear liquid that helps force out any contaminants. Macrophages also produce growth factors that help repair the wound(4).

Reduces Pain

The action of licking also helps reduce pain. This is true whether the animal is licking the site of the wound or somewhere or something else.

The act of licking causes the release of calming endorphins. These hormones help ease anxiety and relax the body. But they also play an important role in pain management by interrupting pain signals sent to the brain via nerve pathways. These hormones act indiscriminately on pain pathways, which means your pet receives the pain reduction benefit regardless of what they are licking and what is causing them pain.

The Drawbacks to Wound Licking

Of course, if wound licking was entirely beneficial, things like e-collars and wound wraps wouldn’t exist. The fact is, sometimes wound licking can be detrimental to healing. This is true when licking is unable to cleanse the wound of all bacteria, when the licking is obsessive enough to slow the healing process, or when the wound is very deep or contains stitches.

Not All Bacteria Will Be Killed

Many of the same studies that have shown that animal saliva has antibacterial properties have also revealed that the effectiveness of these properties is limited for some types of bacteria.

Staphylococcus, for instance, appears much less susceptible to salivary antibiotics than other pathogens. This type of bacteria is very common on companion animals, which makes it likely that this kind of infection will develop in a wound regardless of whether the animal licks the site or not.

The antibiotic properties of saliva are also limited by the depth of the wound and the overall health of the animal.

If the wound is very deep, then no amount of licking is going to remove or neutralize all the bacteria present within it. And if the animal is not healthy, to begin with, there is a good chance their saliva doesn’t contain as many beneficial properties as needed to take on an infected wound.

Most companion animals suffer from bacterial imbalances due to poor diets, overmedication, and the general toxicity of the modern world. These imbalances affect not only the microbes in their gut but the probiotic load in their mouth. Without the right balance of facultative anaerobes, the concentration of antibacterial substances in the saliva is likely to be much lower than what is needed to effectively cleanse a wound.

Obsessive Licking Can Slow Healing

Even more worrisome is the fact that licking can quickly become obsessive, especially in companion animals who have a lot of downtime and experience higher rates of stereotypic behaviors than their wild cousins.

As we mentioned above, when a dog or cat licks their wound, it releases feel-good endorphins. Once enough endorphins are released to lower the pain of the wound, the pet will no longer feel the need to keep licking. But, if the pet is experiencing other stressors that can be calmed by endorphins, they will continue licking to placate these anxieties, as well.

This licking can quickly become obsessive to the point that the animal cannot stop. When obsessive licking occurs on normal, healthy skin, it can cause hot spots. When it occurs on a wound, it will keep the area moist and ripe for infection while preventing the tissue from healing.

Can Tear Our Stitches

Licking a scrape or cut will rarely cause problems for our pets. But licking a deep wound can be problematic.

Wild animals will resort to licking wounds no matter how severe because they have no other recourse. This method is not always enough to prevent infection or to keep the animal alive. Our pets, luckily, do have better options for dealing with severe injuries.

If your pet has to go to the vet to have their wound treated and sutured, then letting them lick it afterward is not a good idea. Not only is there a potential they will introduce some of those antibacterial resistant pathogens into what is now a sterile wound, but they are also very likely to rip out the stitches.

Under the best circumstances, ripped-out stitches will result in an ugly scar and slower healing. In the worst, your pet could expose deep muscle or internal organs to the outside world. This is especially likely if the stitches were put in after surgery.

When and How to Control Your Pet’s Wound Licking

If your pet has suffered a minor scrape, scratch, or otherwise shallow wound, then letting them lick the area isn’t likely to cause any problems. Just be sure to keep an eye on the situation to assure the licking doesn’t become obsessive.

After a day or two of attention, they should start to leave the wound alone. If the wound starts to dry and scab and your pet starts liking it again and removing the dried tissue, this is a good sign they are licking not to help the wound heal, but out of boredom or to release more of those feel-good hormones.

If distracting the pet isn’t enough to keep them from continuing to lick the wound, then it’s time to step in and prevent licking. If your pet has a deep wound, especially one that has been treated by a vet, then you should work to prevent licking from day one.

Some effective ways to keep your dog from licking their wounds include:

• Exercise – Get your dog out of the house or bust out the wand toys to get your cat moving. Often, when a pet continues to lick a minor wound it’s because they are bored and the endorphins provide some relieving stimulation. If you can get them distracted and tired, they’ll often forget about the wound entirely. Of course, if your pet just had surgery, exercise is not a good choice.
• Give Them Something Else to Lick – If your dog is licking out of boredom or because they’ve developed a dependency on those feel-good endorphins, try giving them something else to lick. A Kong stuffed with peanut butter (for dogs) or wet food and then frozen makes a great, long-lasting lick treat.
• Use a Recovery Collar – Recovery collars are similar to traditional Elizabethan collars, but allow the pet to move more freely. These “neck donuts” work very well for wounds on the stomach, back, and rear end. They are not as effective for wounds on the legs and paws. For these, you may have to use an e-collar to be sure your pet can’t reach the site.
• Use a T-Shirt – Wounds on the body can often be protected from excess licking by putting an old shirt on your pet so they can’t physically reach the wound with their tongue.
• Use a Muzzle – If your dog has been trained to accept a muzzle, this can be an effective way to keep them from licking those easy-to-reach wounds. Just be sure they are comfortable in the muzzle and that you use a wide basket that allows them to pant and drink water freely while wearing it.

Wrapping wounds and using taste deterrents are not options we recommend. When a wound is wrapped longer than it should be, it tends to stay moist, which makes it more prone to infection. Many dogs will just chew the wrap off anyway, further aggravating the wound below.

Taste deterrents, whether commercial or homemade, tend to be far less effective than advertised, especially for the determined chewer. And they have the potential to irritate open wounds.

The good news is that most wounds your pets will experience are likely to be minor. This means that so long as you keep an eye on them and intervene if necessary, you’re fine to let your pet practice their instinct and heal their wound by licking it.

By Carrie Hyde, The Spaw Pet Life Coach | March 20, 2023

Written for The Spaw by Sara Seitz, Professional Freelance Writer, and Novelist with Pen and Post

Carrie Hyde is the founder, owner, and Pet Life Coach of The Spaw in Tustin, CA. Carrie’s extensive experience and understanding of pet nutrition and coaching enabled her to create The Spawdcast, a podcast dedicated to educating pet parents and pet industry professionals on ALL the options available to their pets. Her mission is to open pet-owners eyes to the questions they may not even know to ask, to shine a light on the many myths that have been part of pet care for decades, and to offer whole solutions for their pets. Carrie Hyde is a certified pet nutritionist with the goal of helping pet parents & pet professionals with a new understanding of how to care for pets in a “whole and natural” way.