Quick Answer
No, it is generally not recommended to lick a cut or wound. Licking can introduce bacteria, viruses, and other microorganisms into the cut that can cause infection. Saliva also contains enzymes that can damage tissues and delay healing. Instead, you should clean cuts with soap and water or an antiseptic, apply antibiotic ointment, and cover with a sterile bandage. See a doctor for deep cuts or those showing signs of infection like redness, swelling, warmth, and pus.
Most of us have likely licked a paper cut or small wound at some point. You may have thought this was helpful to clean or disinfect the cut. However, research shows licking a wound to clean or treat it can do more harm than good in most cases.
Licking introduces saliva into the cut or laceration. Saliva contains a number of components that may aggravate the wound and delay healing. The mouth is also full of bacteria and other microorganisms that can cause infection when introduced into broken skin.
For these reasons, doctors and health experts warn against the practice of licking cuts and recommend alternative first aid options. Treating cuts properly reduces healing time and prevents complications like infection.
Potential Risks of Licking Cuts
Here are some of the main concerns with licking wounds:
Infection
The human mouth contains over 700 species of bacteria, as well as viruses, fungi, and protozoa. Many of these microorganisms are opportunistic pathogens that can cause infection when entering the bloodstream through a wound.
Studies show saliva contains bacteria including Streptococcus, Staphylococcus, and Clostridium. Staphylococcus aureus is a common source of wound infections. Viruses found in saliva which could infect a cut include herpes simplex virus (cold sores), Epstein-Barr virus (mononucleosis), cytomegalovirus, hepatitis B, and others.
Therefore, licking introduces pathogens into vulnerable tissue that can lead to infection. This delays healing at best and may become a dangerous, systemic infection at worst.
Irritation and Damage
In addition to microorganisms, saliva contains enzymes meant to start digesting food. These include salivary amylase and lipase. When these enzymes contact broken skin and tissues, they can cause damage and irritation. The foreign enzymes may digest healthy cells and proteins, causing further injury to the wound site.
The results can be pain, discomfort, and disruption of the complex cell signaling process that facilitates healing. Damaged tissue may die, turn into an ulcer, or leave a larger scar.
Delayed Healing
As discussed above, licking a cut adds microorganisms and enzymes that can aggravate the wound. The resulting infection and tissue injury slow the body’s natural healing mechanisms.
Healing a cut or scrape involves four overlapping phases:
- Hemostasis – Blood clots to stop bleeding
- Inflammation – White blood cells fight bacteria as tissues release signals to start healing
- Proliferation – New tissue forms to mend wounds
- Remodeling – Collagen reforms to strengthen repaired tissue
When licking interferes with these controlled processes, it delays reforming skin over the damaged area. Healing takes longer.
Potential Benefits of Licking Minor Cuts
Despite the risks, there may be some potential advantages to licking small, clean, uncomplicated wounds in ideal conditions. Possible benefits include:
Cleansing
Saliva contains water and enzymes that can help flush out dirt, debris, and contaminants from a fresh cut. This may reduce the risk of some infection when no other cleaning options are available.
Of course, rinsing with potable water would be even safer and more effective. Alternatively, gentle cleansing with mild soap and water is recommended for wound care.
Numbing
Nerve endings in the tongue may transmit signals that block pain sensations from a minor cut or scrape. The slightly numb feeling after licking a wound may temporarily reduce discomfort.
However, consult a doctor for cuts requiring stitches or at risk of infection rather than relying on saliva for anesthesia. Medical-grade topical analgesics are also safer and more effective pain relievers.
Protection
A thin film of saliva over a cut may offer some physical barrier against abrasions or contact irritation. Licked wounds can be covered with a sterile bandage for better protection.
Infection Prevention
A 2018 study found antimicrobial compounds called histatins in human saliva. Histatins disrupt bacterial cell membranes and may combat some microbes that cause infection. However, saliva remains a source of dangerous pathogens itself.
While licking wounds to fight infection is still ill-advised, researchers propose medications containing histatins could be derived from saliva components.
Alternative Wound Care Options
Instead of licking deeper cuts or puncture wounds, follow these evidence-based first aid guidelines:
Clean and Flush
Rinse cuts with clean, running water to remove debris and flush out bacteria. Gently cleanse wounds with mild soap and water when available. Avoid harsh scrubbing which can damage tissue.
An antibiotic ointment or solution like povidone-iodine may also be used to cleanse wounds under medical supervision.
Apply Antibiotic Ointment
After cleansing, apply an antibiotic cream or ointment like Bacitracin, Neosporin, or Polysporin. These provide a protective antibacterial barrier while keeping the wound moist to promote healing.
Cover with a Sterile Bandage
Cover the antibiotic ointment with a sterile adhesive bandage or dry clean cloth. This protects wounds from re-injury or outside contamination while absorbing drainage. Change bandages daily or whenever soiled.
Watch for Signs of Infection
Monitor cuts for increased redness, swelling, warmth, pus, red streaks, fever, or worsening pain. These are signs of infection requiring medical treatment. Skin glue or stitches may close deeper cuts.
Get a Tetanus Shot
Dirty, deep puncture wounds may require a tetanus immunization if it has been over 5 years since the last shot. Tetanus is a severe bacterial infection that causes painful muscle spasms.
See a Doctor for Severe Cuts
Immediately call your doctor for medical care with cuts:
- Requiring stitches
- With pieces of debris embedded
- Actively bleeding after 10 minutes of pressure
- More than 1/4 inch deep
- On joints, hands, or genitals
Proper wound assessment, cleaning, and dressings promote healing. Follow up with a physician promptly for severe lacerations or concerning symptoms.
Special Cases of Licking Wounds
Certain animals in the wild will lick wounds instinctively as an adaptive self-care behavior. For example, dogs and cats lick minor scrapes using their rapid, fine grooming motions. Their saliva may help cleanse debris and apply antimicrobial compounds found in animal saliva to control infection.
However, excessive licking can still delay healing. Veterinarians advise monitoring the area and using an Elizabethan collar to prevent re-injury from licking if necessary. Keep pets up to date on vaccines like rabies and tetanus that could be transmitted through a bite.
For human children, licking minor boo-boos can also be a self-soothing habit. However, clean the area and apply a proper bandage to reduce infection risk. Distracting your child when practical and using positive reinforcement may help break the licking habit. Consult your pediatrician for proper wound care.
Key Points
– Licking deeper cuts or wounds is not recommended, as saliva introduces infection risk. However, licking tiny, clean scrapes may offer some benefits.
– Potential risks of licking wounds include infection, irritation, tissue damage, and delayed healing.
– Alternatives like rinsing, antibiotics, bandages, and tetanus shots promote proper wound healing and prevent complications.
– While animals may instinctively lick small wounds, excessive licking should be discouraged to support healing. Use alternatives for human children as well.
– When in doubt, seek medical care for safe cleansing and treatment of more severe cuts, especially those requiring stitches or showing signs of infection.
Conclusion
Licking a minor paper cut or scrape may seem harmless, but has risks. Saliva can introduce dangerous bacteria into wounds and contains enzymes that damage tissue. The slight numbing effect is minimal.
Overall, licking cuts and wounds delays healing and raises infection risk. Proper first aid like washing, antibiotic ointment, bandages, and medical care will improve results. Only lick tiny, clean wounds where needed for cleansing and comfort. Otherwise, avoid licking cuts and follow standard wound care guidelines instead for optimal healing.