Compatibility of Tranexamic Acid and L-Ascorbic Acid in Formulations

Yes, Tranexamic Acid and L-ascorbic acid can be used together in the same cosmetic formulation.

Both ingredients are water-soluble, which is a compatible characteristic for formulation. However, the key consideration is the pH level required for L-ascorbic acid.

L-ascorbic acid is most stable and effective in formulations with a low pH, typically between 2.0 and 4.0. The FDA requires cosmetic products applied to the skin to have a pH of at least 3.5. Therefore, formulations containing L-ascorbic acid are usually formulated in the pH range of 3.5-4.0.

Tranexamic Acid is stable over a wider pH range, from 3 to 8. The required low pH for L-ascorbic acid falls within the stable range for Tranexamic Acid.

When formulating, it is important to consider the inherent instability of L-ascorbic acid in water-based solutions, especially regarding oxidation. Proper formulation techniques, such as mixing L-ascorbic acid in the final step at a temperature below 30°C, and potentially using antioxidants or chelating agents like Disodium EDTA, are crucial for maintaining the stability and efficacy of L-ascorbic acid.

Both standard Tranexamic Acid and Nano-TXA™ (a nano emulsion form of Tranexamic Acid) can be used. Similarly, various grades of L-ascorbic acid powder (Standard, Fine, Ultra-Fine) are available, differing mainly in particle size and ease of dispersion.

In summary, while compatible in terms of pH range, successful formulation requires careful attention to the stability requirements of L-ascorbic acid.