How Caffeine works 카페인
Caffeine is a vasoconstrictor — it temporarily narrows the small blood vessels near the skin surface, which reduces the look of puffiness and the bluish shadow those vessels cast through thin under-eye skin. It also has mild antioxidant activity. The vasoconstriction is well established pharmacologically, though controlled evidence that a topical caffeine eye product measurably reduces puffiness is thinner than the category's confidence suggests — and whatever effect there is wears off over a few hours.
| Acts on | the look of under-eye puffiness and shadow |
|---|---|
| Evidence | Moderate |
Caffeine guide →Effective % & pH →
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🙋 People also ask
How long does Korean skincare take to work?
Most skincare, Korean or otherwise, needs time. Hydration benefits can appear quickly, but visible changes in tone, texture or fine lines typically take several weeks to a few months of consistent use, roughly one skin cycle or more. Sun protection and patience matter more than any single product.
Does Korean skincare work for deeper skin tones?
The skincare does — hydration, barrier support and soothing actives are not tone-specific. The friction points are mineral sunscreens that leave a cast and a colour-cosmetics shade range that has historically been narrow.
✍️ Written & reviewed by the KoreaPlus Editorial team — dermatologist-informed, cosmetic-science researched & source-cited. Last reviewed: 2026-08-23.
General educational information using cosmetic structure-function wording — not medical advice. Always patch-test new actives. © KoreaPlus.