Lactic Acid 10% + HA is an alpha hydroxy acid solution that offers effective exfoliation targeted at the skin’s surface. It is supported with purified Tasmanian pepperberry extract, a known anti-irritant. This water-based serum is ideal for dry skin types. This pH of this formula is approximately 3.8. Lactic Acid has a pKa of 3.8 and pKa is the most important aspect to consider in formulating with acids. pKa implies acid availability. When pKa is close to pH, there is an optimal balance between salt and acidity.