Caffeine is a methylxanthine commonly used in topical skincare at low concentrations to provide antioxidant activity and temporary vasoconstriction, often marketed for reducing under-eye puffiness and the appearance of dark circles. At 0.5% it is a mild active that may also contribute to a temporary tightening or de-puffing effect.
| Reported effect | How often | Notes |
|---|---|---|
| Mild local irritation or stinging | Uncommon | Transient redness or tingling, more likely on sensitive or compromised skin. |
| Contact dermatitis / allergic reaction | Rare | Allergy to caffeine or co-formulated ingredients can cause localized rash or itching. |
| Dryness | Rare | Occasionally reported, often related to other formulation components rather than caffeine itself. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.