- Q: Can I use Numbuzin No.9 alongside active Vitamin C or Retinol? - A: Yes. The NAD+ and peptide matrix in No.9 complements both Vitamin C and Retinol. For optimal absorption, apply Numbuzin No.9 immediately after cleansing/toning, followed by your targeted active serums. - Q: Is this essence suitable for oily or acne-prone skin? - A: Absolutely. The formula features a weightless, fast-absorbing fluid-gel texture that hydrates and firms without clogging pores or leaving an oily film. - Q: Should I apply this with a cotton pad or hands? - A: Direct application using clean hands is recommended. Pressing the liquid into the skin with warm palms minimizes product waste and enhances the absorption of bio-active molecules.