The Knowledge Hub

Sodium Ascorbyl Phosphate

Sodium Ascorbyl Phosphate

Summary: A stable, water-soluble vitamin C derivative with antioxidant properties and clinically supported anti-acne benefits.

Published on: 12/05/2025

Sodium Ascorbyl Phosphate (SAP) is a stable, water-soluble derivative of vitamin C offering superior formulation stability, antioxidant effects, and clinically demonstrated anti-acne benefits [1].

Formulation Advantages & Skin Benefits

  • Enhanced Stability: SAP exhibits greater stability than L-ascorbic acid in aqueous solutions, particularly due to its resistance to oxidation [2]. ​

  • Anti-Acne Effects: Clinical studies have demonstrated that SAP possesses antimicrobial properties effective against acne-causing bacteria, making it beneficial for individuals with acne-prone skin [1]. ​

Safety and Tolerability

Sodium Ascorbyl Phosphate is generally well-tolerated. In animal studies, high-dose dermal application caused only mild, temporary irritation, and eye exposure resulted in slight, reversible conjunctival irritation. Sensitization potential was low, with only mild reactions observed in a small percentage of animals during initial testing and none upon re-challenge [3].

Conclusion

Sodium Ascorbyl Phosphate stands out among vitamin C derivatives due to its potential anti-acne effects. It is also more stable than L-ascorbic acid in formulations, particularly because it resists oxidation and does not degrade as readily in aqueous environments.

References

  1. Klock, J. et al. (2005). Sodium ascorbyl phosphate shows in vitro and in vivo efficacy in the prevention and treatment of acne vulgaris. International Journal of Cosmetic Science, 27(3), 171–176.https://pubmed.ncbi.nlm.nih.gov/18492184/

  2. Sasidharan, O., Gholap, A., & Rastogi, R. (2023). A review of clinical efficacy of topical vitamin C and its derivatives. Pharmaceutical Science and Technology, 7(2), 20–26.
    https://pdfs.semanticscholar.org/ed04/b17732da7c54b3ed727b1f66aad421f6fa94.pdf

  3. Cosmetic Ingredient Review Expert Panel. (2024). Safety assessment of ascorbic acid and ascorbates as used in cosmetics. Cosmetic Ingredient Review, Re-Review for Panel Consideration, September 6, 2024.
    https://www.cir-safety.org/sites/default/files/Ascorbic%20Acid.pdf