Why does it take longer for wounds inside your body to close than wounds outside it?


Since external wounds are exposed to, well, the outside, shouldn’t they heal slower? Why is it that internal wounds take longer and sometimes may not even heal at all without medicine, like fissures and canker sores?

In: Biology

It generally has to do with moisture. If the wound is wet the infection has an easier time to survive.

Drying out a wound reduces the ability of the bacteria to survive. In fact, this is why dries meats do not rot. And why mummies exist.

Moisture slows down clotting, which is responsible for stopping bleeding and starting the healing process. This is why suicidal individuals may slit their wrists in a bathtub full of water; submerging the wound in water will reduce the clotting rate, increasing the chance that the victim “succeeds”/bleeds out before they are found/saved.


Except for the outer layers of skin, your body is pretty wet. It likes being wet. The skin keeps the wetness in and the dryness out.

When you get wound on the outside of your body, the protective layer of your skin is broken, and the cells that thrive in wetness are now exposed to the dry outside environment. They don’t like it.

When you put something like neosporin and a non-sticking bandage on a wound, that dressing is acting like your skin. The cells are happily back in their wet environment and can function and heal properly—quicker and with less scarring.