Addressing Stinging and pH Adjustment in Your Formula

Based on the feedback regarding your formula for melasma, freckles, and dark spots:

Stinging Sensation:

The stinging you experienced is likely due to the high concentrations of Tranexamic Acid and Azelaic Acid in your formula. These are effective whitening agents but can cause irritation, especially at the percentages you used.

• Recommendation: The safest way to address this is to reduce the concentration of Tranexamic Acid and Azelaic Acid. Start with lower percentages and gradually increase them as your skin builds tolerance.
• Adding FastRelief™ is not recommended as it only masks the stinging sensation and does not prevent irritation or potential allergic reactions.
• While a preservative allergy was mentioned as a possibility (specifically to Phenoxyethanol SA), it is less likely the cause if you have used other products with this preservative without issues.

Using a formula that causes irritation can damage your skin in the long run, which is counterproductive to treating melasma.

pH Adjustment:

To lower the pH of your formula from 6.5 to your target of 5.5, you will need to add an acidic ingredient.

• Recommendation: Use a cosmetic-grade acid such as Citric Acid or Lactic Acid. Add the acid in very small amounts, mix well, and measure the pH with a pH meter after each addition until you reach the desired pH of 5.5.

Always test the formula on a small area of skin first to ensure tolerance before applying it widely.