Why is phosphoric acid an ingredient of the 12.5% Minoxidil Solution?
A. Phosphoric acid is an inorganic acid commonly used in cosmetic products to enhance their water retention. As an ingredient in the 12.5% Minoxidil Solution, the phosphoric acid serves several important functions. (1) It helps to stabilize the minoxidil, which is more soluble in an acidic base. (2) Retaining water in the 12.5% Minoxidil Solution has an effect similar to hydrating the scalp and enhances the absorption of minoxidil. And (3), Stabilizing the acidity of the 12.5% Minoxidil Solution balances the pH to approximate the pH of the skin, which is optimal at a pH of ~5.5. This degree of acidity helps the skin to ward off the advances of harmful bacteria and fungi.
