Ingredient caution: retinol/retinoids might cause dryness, peeling, redness, purging and sun sensitivity; humectants such as hyaluronic acid/glycerin are usually gentle but might feel sticky or tight if not sealed with moisturiser. Do a patch test before applying. Retinol is not advised for pregnant or breastfeeding women unless approved by a doctor. First-time users should start 3–4 times a week at night, avoid layering with exfoliating acids, and use sunscreen daily. Apply on slightly damp skin and follow with moisturiser if dryness occurs. Stop use if irritation persists.