Ingredient caution: salicylic acid/BHA might cause stinging, dryness, peeling, redness and increased sun sensitivity; azelaic acid might cause tingling, dryness or redness in sensitive skin; sulfur/zinc-based oil-control ingredients might feel drying or tight on already dry skin; fragrance, essential oils or fragrance allergens might trigger redness, itching or allergic irritation. Do a patch test before applying. First-time users should start 3–4 times a week, avoid using it with retinol or other exfoliating acids in the same routine, and apply sunscreen daily. First-time users should start 3–4 times a week and pair with sunscreen, because pigmentation care works best with UV protection. Use a moisturiser and reduce frequency if the skin feels tight or flaky. Avoid this product if you have fragrance allergy, eczema-prone skin or a damaged barrier. Stop use if irritation persists.