The Ordinary Alpha Arbutin 2% + HA is a water-based serum formulated to target hyperpigmentation and uneven skin tone. It combines a high 2% concentration of alpha arbutin with hyaluronic acid for enhanced delivery and hydration benefits. Alpha arbutin is known to be sensitive to degradation when exposed to water, but this formula is specifically pH-balanced to minimize degradation and maintain stability. The product may experience natural color changes when exposed to sunlight or increased temperatures, but this does not affect its efficacy or safety. It can be used both in morning and evening skincare routines.