A pimple forms when a pore becomes clogged with excess oil, known as sebum, and dead skin cells. This blockage creates an environment where a common skin bacterium, Cutibacterium acnes, can multiply, triggering an immune response. The resulting inflammation and buildup of material underneath the skin’s surface is what creates the visible, raised bump. The white or yellow material that collects at the center of an inflamed pimple is the body’s direct response to this localized skin infection.
What Pus Is Made Of
Pus is the whitish-yellow substance inside a pimple, a byproduct of the body’s defense system fighting trapped bacteria. It is a protein-rich fluid composed primarily of dead white blood cells, specifically neutrophils. These cells travel to the infection site to engulf and destroy the invading bacteria, dying in the process.
Pus also contains dead bacteria, dead skin cells, and the sebum and debris that initially clogged the pore. This mixture of biological material is contained within the inflamed hair follicle, creating pressure against the surrounding skin.
The Body’s Process of Healing
When a pimple is left alone, the body resolves the infection and eliminates the pus internally. The inflammatory response gradually slows down once the immune system contains the bacterial threat within the follicle. This reduction in inflammation is the first step toward natural healing and allows the body to begin its cleanup process.
The fluid component of the pus is slowly reabsorbed by the body’s lymphatic system and surrounding blood vessels. This process drains the liquid material back into circulation to be safely filtered and processed. Specialized white blood cells called macrophages then arrive at the site to act as scavenger cells.
Macrophages break down and consume the remaining solid debris, such as dead neutrophils and bacteria. This allows the lesion to shrink and flatten naturally over a period of days to a few weeks, depending on the pimple’s depth. In some superficial pustules, the skin may thin and rupture, allowing the pus to drain to the surface before healing over. Internal absorption ensures the infected contents are safely eliminated without external trauma to the skin.
Comparing Natural Resolution to Popping
Allowing a pimple to heal naturally minimizes the risk of long-term skin damage by avoiding external trauma. Natural resolution usually results in temporary post-inflammatory hyperpigmentation (PIH) or redness, which is a temporary discoloration that fades relatively quickly. The underlying tissue structure remains intact, significantly lowering the chance of permanent scarring.
Manually popping a pimple, however, carries several risks that can worsen the outcome. The pressure from squeezing can rupture the follicle wall deep beneath the skin, forcing the infected pus and bacteria into the surrounding dermal tissue. This can dramatically increase the inflammation, lead to a larger, more painful blemish, and potentially spread the infection to neighboring pores.
Forcing material deeper into the skin creates a more significant injury, which increases the likelihood of developing permanent atrophic scars, such as icepick or boxcar scars. Popping can also delay the healing process, turning a spot that might resolve in a few days into a wound that takes two weeks or more to fully recover. The risk of creating a lasting mark on the skin is the primary reason dermatologists advise against manual extraction.