Compatibility of PE-1 Aqua and ODA-White Plus

Based on the product information:

• PE-1 Aqua is a penetration enhancer specifically designed for water-soluble active ingredients. Its description explicitly states that using it with oil-soluble active ingredients will reduce the absorption efficiency of the oil-soluble active.
• ODA-White Plus is a whitening active ingredient that is oil-soluble.

Therefore, mixing PE-1 Aqua and ODA-White Plus in the same formula is not recommended as it would likely reduce the effectiveness of ODA-White Plus.

Using them in separate formulas and applying them sequentially is a suitable approach to avoid this incompatibility. As suggested in the previous reply, applying them separately with a short waiting period between applications helps ensure each ingredient can work effectively without interfering with the other.