Cosmetics Formulation Development

To make melasma treatment cream to fade, use Zinc Sulfate ? Question 2, if yes, is seen in the description of the substance saying 10-15 % will see good results But the instructions say that no more than 5% will be irritating. How much should you wear?

Hello Zinc Sulfate FDA allows maximum use of 1%, if higher than this. The product must be registered as a drug. Cannot be sold as cosmetics