The sight of green discharge from a cut or wound is concerning, but it signals that your body is actively battling a bacterial infection. This fluid, known as purulent exudate or pus, is a byproduct of the immune system’s defensive response. When the skin breaks, bacteria can colonize the area, triggering an intense biological fight. The resulting green hue indicates specific microbial processes occurring within the wound.
The Biological Explanation for Green Discharge
The fluid in an infected wound is largely composed of neutrophils, a type of white blood cell sent to destroy invading microorganisms. After these immune cells neutralize bacteria, they die and accumulate with dead tissue, forming the thick, opaque substance known as pus.
While pus is typically yellowish-white, the unique green color is often linked to the presence of the bacterium Pseudomonas aeruginosa. This opportunistic bacterium produces a characteristic blue-green pigment called pyocyanin. Pyocyanin stains the pus and sometimes the dressing a vivid shade of green.
Infections caused by P. aeruginosa may also be accompanied by a noticeably sweet or fruity odor. The presence of green pus is a clear sign that significant bacterial colonization has taken hold and requires attention.
Assessing the Severity of Wound Infection
The appearance of green discharge confirms an infection, but other symptoms determine the level of risk. Localized signs are confined to the area immediately surrounding the cut. These include increasing pain, swelling (edema), and skin redness (erythema) that spreads outward from the wound edges. The skin around the cut may also feel warm to the touch, indicating increased blood flow.
A more serious concern arises when the infection spreads beyond the immediate site and becomes systemic. Signs of a systemic infection include fever or chills. Another concerning sign is the appearance of red streaks extending from the wound toward the nearest lymph nodes, known as lymphangitis. If you experience generalized feelings of being unwell, such as nausea or persistent fatigue, the infection may be progressing and requires prompt medical evaluation.
Immediate Home Care Steps
The first action upon noticing green discharge is to thoroughly clean your hands to prevent further contamination. Gently rinse the wound under running tap water or with sterile saline solution to flush away the discharge and loose debris. Wash the surrounding skin with mild soap, but avoid scrubbing the soap directly into the wound bed, as this can cause irritation.
After cleaning, gently pat the area dry and apply a fresh, sterile dressing. Change this dressing at least once a day, or immediately if it becomes wet or soiled, to maintain a clean environment. Close monitoring is necessary to track the infection’s progression. If redness or pain worsens, or if systemic symptoms like fever or red streaking appear, seek medical care without delay.