What should you know about COSRX hyaluronic acid essence?

Hyaluronic acid is a water-attracting substance used in skincare. An essence is a lightweight leave-on product, usually applied after cleansing and before a moisturiser. It can temporarily improve the feeling of dryness, tightness, or rough texture by adding water to the outer skin layer. It does not replace a moisturiser, sunscreen, or treatment for eczema, infection, or an allergic rash. Results depend on the rest of your routine and your skin barrier.

Apply a small amount to clean, slightly damp skin, then follow with a moisturiser to reduce water loss. Introduce it gradually if your skin is reactive. Check the product label for the full ingredient list, because a reaction may come from a fragrance, preservative, or another ingredient rather than hyaluronic acid itself. Avoid putting it into an open wound or directly into the eyes. You can read more about [Hyaluronic Acid](/materials/hyaluronic-acid/) and how a medical [Hyaluronic Acid Injection](/treatments/non-surgical-orthopedics/hyaluronic-acid-injection/) differs from a cosmetic essence.

Stop using the product and seek medical advice if you develop spreading redness, marked swelling, blistering, severe burning, or persistent itching. Urgent help is needed for facial or lip swelling, wheezing, trouble breathing, or faintness after application. Ongoing dryness, cracking, or a rash may need assessment for dermatitis or another skin condition.

Ask whether your symptoms fit simple dryness or dermatitis, whether any listed ingredient should be avoided, and what moisturiser or treatment suits your skin barrier.