Caffeine

Stimulates circulation and reduces puffiness and dark circles.

Also known as: 1,3,7-Trimethylxanthine; Coffee extract; Caffeine anhydrous; Same name.

What it is

Caffeine is a naturally occurring alkaloid found in coffee beans, tea leaves, and other plants. In skincare, it's typically derived from coffee extract or synthesized as caffeine anhydrous.

What it does

Caffeine acts as a vasoconstrictor, narrowing blood vessels to reduce fluid retention and puffiness—especially around the eyes. It also has mild antioxidant properties and may improve microcirculation, helping to brighten dark circles and give skin a more alert appearance. When applied topically, it does not produce systemic stimulation.

The evidence

Strong clinical evidence supports its efficacy for reducing under-eye puffiness and dark circles; multiple peer-reviewed studies confirm vasoconstriction and improved appearance within 15–30 minutes of application. Evidence for broader anti-aging or antioxidant benefits is moderate and less consistent.

Best for

Tired, puffy, or dark-circled eyes; anyone seeking a quick depuffing and brightening effect before events.

Pairs well with

Hyaluronic acid, peptides, niacinamide, and other hydrating or antioxidant actives; works well in eye serums and creams.

Use cautiously with

No major conflicts; generally compatible with most skincare ingredients. Avoid excessive use in very sensitive or reactive skin.

Cautions

Caffeine is generally well-tolerated topically; rare sensitivity or irritation possible in very reactive skin. Not sun-sensitizing. Safe in pregnancy at typical skincare concentrations, but consult a provider if concerned.