Vitamin C tends to work faster on fresh, recent spots, while alpha arbutin is more consistent over time on marks that have been there longer – for tone that's stuck around, combining both (vitamin C in the morning, alpha arbutin at night) works best.

• Vitamin C is a strong antioxidant that brightens quickly but can be less stable and more irritating for sensitive skin.
• Alpha arbutin works more gradually by blocking the enzyme behind pigment production, so it's gentler over the long run.
• Combining both means you get fast surface brightening and long-term prevention working together.
• Layer vitamin C in the morning under SPF, and save alpha arbutin for your evening routine.
• Neither works without daily SPF – sun exposure undoes both actives equally fast.

No SPF, impatience, and using the wrong active for the wrong type of pigmentation are the three biggest culprits – get the diagnosis right and give it consistent time before deciding it's not working.

• Mistake 1: skipping SPF – any sun exposure quietly undoes whatever your brightening active is doing.
• Mistake 2: impatience – brightening actives like alpha arbutin genuinely need consistent, ongoing use to show visible change.
• Mistake 3: using the wrong active – post-inflammatory marks, sun damage and melasma each respond differently, so the diagnosis matters.
• Alpha arbutin is a safer starting point for post-inflammatory marks and darker skin tones specifically.
• Consistency beats intensity – daily use of one well-matched active outperforms switching products every few weeks.