Answer:

Physiological saline (0.9% NaCl) is an isotonic solution with an osmotic pressure close to that of human bodily fluids. Its gentle nature, which prevents stinging or mucosal damage, makes this solution commonly used in medicine for safe disinfection, cleaning, and sterilization.

While not a dedicated skincare product, physiological saline offers mechanical cleansing properties that can provide certain benefits for the skin when used appropriately. Washing your face with physiological saline gently removes dirt, excess oil, dead skin cells, and sebum, helping to clear pores. This method suits individuals with sensitive skin, those prone to irritation from cleansers containing fragrances or alcohol, or skin experiencing inflammatory acne.

With mild antiseptic capabilities, physiological saline also helps reduce inflammation and limit the growth of acne-causing bacteria, particularly in areas with redness or small open wounds. This product can support the treatment of acne during severe inflammatory stages or when skin is peeling due to medication. Doctors also recommend using physiological saline temporarily after cosmetic procedures like chemical peels, laser treatments, or microneedling, when it is necessary to avoid foaming products for the first few days to allow the skin to recover.

However, using physiological saline to wash your face is only a temporary supportive measure and cannot completely replace facial cleanser. This solution does not contain active ingredients to remove oil and cosmetic residue. If you only wash with saline, dirt and makeup can remain in pores, potentially leading to comedones or seborrheic dermatitis.

Overusing physiological saline can also damage the skin barrier. When used frequently, especially on dry or sensitive skin, salt can draw out moisture, leading to dehydration, flaking, and increased irritation from sun, dust, and bacteria. The risk of irritation is even higher if you are currently using potent active ingredients like retinol, acids, BHA, or topical antibiotics.

To effectively control acne, you need to maintain a basic skincare routine, including gentle facial cleansing two times daily and using prescribed medications or specific products as directed by a doctor. A treatment plan should combine topical medications, oral medications, products to control sebum, deep cleansing, and restorative moisturizing with creams containing ceramide, hyaluronic acid, or panthenol. Limit touching your face, picking at acne, staying up late, and consuming greasy, sugary foods.

If you choose to use it, select 0.9% physiological saline from reputable pharmaceutical companies with medical certification labels. Avoid mixing saline at home, as it may not be sterile, and incorrect concentration estimates can make the solution too salty, causing stinging and disrupting the skin's protective lipid layer.

For large bottles, pour the solution into a clean cup, avoiding contact between your hands or cotton pads and the bottle opening to prevent bacterial contamination. If using small bottles, finish them within one to two days after opening. You should only wash your face with physiological saline one time daily or two to three times a week for gentle cleansing before using a facial cleanser. Afterward, apply a moisturizer to restore the natural moisture barrier and use sunscreen during the day to protect your skin. If you experience tightness, stinging, flaking, dryness, dullness, or tiny bumps after use, stop immediately and switch to a milder product.

Dr. Quach Thu Trang

Department of Dermatology

Tam Anh General Hospital Hanoi