Using 10% PHA Serum with Whitening Agents Daily

Based on general formulation principles, using a serum containing 10% Gluconolactone along with other whitening agents twice daily (morning and evening) might be too much for some skin types, especially when first starting.

Gluconolactone is a Polyhydroxy Acid (PHA). PHAs are known for being gentler exfoliants than AHAs or BHAs, and they also offer hydration benefits. However, a 10% concentration is still a significant level of active ingredient. Combining it with other potent whitening agents could increase the potential for skin sensitivity or irritation.

It's generally recommended to introduce such active serums gradually into your routine. You could start by applying it only in the evening, or perhaps just a few times per week, to see how your skin tolerates it. If your skin shows no signs of irritation (like redness, stinging, or dryness) after a couple of weeks, you could slowly increase the frequency. However, using it twice daily might still be excessive depending on your individual skin sensitivity and the specific combination of other ingredients in the serum.

Also, remember that using exfoliating acids like Gluconolactone can increase your skin's sensitivity to the sun. Therefore, it is crucial to apply adequate sun protection (sunscreen) every morning, especially if you choose to use the serum during the day.

In summary, while Gluconolactone is gentle, a 10% concentration combined with other actives might require a gradual introduction and potentially not be suitable for twice-daily use for everyone. Pay close attention to how your skin responds.