Sigma-1 receptor

Wound licking is an instinctive response in humans and many other animals to an injury. Dogs, cats, rodents and primates all lick wounds. Saliva contains tissue factor which promotes the blood clotting mechanism. The enzyme lysozyme is found in many tissues and is known to attack the cell walls of many gram-positive bacteria, aiding in defense against infection.

Saliva and healing

The licking of wounds by dogs might have some beneficial effects such as cleaning the wound, but these are likely outweighed by the damage caused by the rough tongue. The beneficial effect of wound licking is the result of the mechanical cleaning effect, the antibacterial effect of saliva, which is even increased by the lysozyme and peroxidase it contains, and the promotion of wound healing by epidermal growth factor.

Risks

There are also many potential risks, as the mouth is a host to many pathogenic organisms, and it is likely that wound licking will introduce infection. In modern medicine, the practice is strongly discouraged.

In culture

Wound licking is a common behavior in animals as well as humans. In literature, it is often used to depict vulnerability and a need for help in characters.

See also

• Animal behavior
• Wound healing
• Saliva