Pus is the result of the body's natural immune system automatically responding to an infection, usually caused by bacteria or fungi. Leukocytes, or white blood cells, are produced in the marrow of bones. They attack the organisms that cause infection.

Is it good for pus to come out?

The bottom line. Pus is a common and normal byproduct of your body's natural response to infections. Minor infections, especially on the surface of your skin, usually heal on their own without treatment. More serious infections usually need medical treatment, such as a drainage tube or antibiotics.

What happens if pus is not drained?

If a skin abscess is not drained, it may continue to grow and fill with pus until it bursts, which can be painful and can cause the infection to spread or come back.