CO2 laser and post-inflammatory hyperpigmentation: what to know

Post-inflammatory hyperpigmentation is extra pigment left after inflammation or injury. It can follow acne, atopic dermatitis, burns, scratches or procedures. CO2 laser intentionally heats and remodels skin, so temporary inflammation is part of healing; in pigment-prone skin, that inflammation may leave darker areas after the surface has recovered.

Existing dark patches or uneven tone do not automatically rule out treatment, but they make diagnosis and timing important. A clinician may first control active acne or dermatitis and decide whether the texture concern justifies the pigment risk. The final appearance depends on laser depth, density, skin tone, healing and sun exposure.

Show the clinician any previous darkening after cuts, acne or cosmetic procedures. Discuss recent tanning, pigment treatments, medicines and active inflammation. Do not treat over irritated or infected skin unless specifically instructed. Your clinician may choose gentler settings, a staged plan or another approach such as a chemical peel, skin brightening treatment or picosecond laser treatment.

During healing, keep the area clean and moisturised as directed, avoid picking or friction, and use broad-spectrum sun protection. Pause exfoliating acids, retinoids and fragranced products until the skin barrier has recovered according to your care plan.

Contact the clinic if redness, heat, pain or swelling is increasing, if blisters or pus appear, or if you develop fever or a spreading rash. Ask for review if darkening becomes sharply worse, new pale patches appear, or healing seems stalled. These changes can reflect infection, prolonged inflammation or pigment alteration that needs a tailored plan.

Ask whether your marks are truly post-inflammatory hyperpigmentation, whether active acne or dermatitis should be treated first, and what laser depth and density are proposed. Ask about a test area, expected colour changes during healing, sun protection, and non-laser options if pigment risk outweighs the expected texture benefit.