Hair & scalp· in 4 products

Caffeine

Also listed as Caffeine (INCI) and 1,3,7-trimethylxanthine

Emerging evidence 0.2% in leave-on hair liquids; 1–5% in eye creams

Caffeine appears in scalp tonics and shampoos marketed for thinning hair, and in eye creams marketed for puffiness. It penetrates skin readily, including through hair follicles.

Shop 4 with caffeine All ingredients

4CfCaffeineHair & scalp

What it does

The short version.

In lab studies caffeine counteracted testosterone's inhibitory effect on hair follicles and prolonged the growth phase. A 2017 open-label randomized study found a 0.2% caffeine liquid was not inferior to 5% minoxidil for men with androgenetic alopecia over six months, though it was industry-sponsored and lacked a placebo. In eye products, caffeine's vasoconstrictive effect may temporarily reduce the look of puffiness.

Emerging evidence

Lab and penetration data are solid, but clinical trials for hair are few, mostly sponsored and lack placebo controls.

In our directory: It’s a key ingredient in 4 products we review, most often eye & lip and moisturizers. Those products are mostly built for hydrating, long-lasting moisture and brightening. In formulas, it most often shares the label with green tea, hyaluronic acid and glycerin.

Reach for it for

Hair growth support Scalp care Firming Antioxidant

Usually a good fit for

All hair types Fine hair Straight hair All skin types

How to use it

Getting it right.

Massage a leave-on caffeine scalp liquid into dry or towel-dried scalp daily, or leave caffeine shampoo on for about two minutes. Pat eye cream gently around the orbital bone.

Layering

Friends & frenemies.

Pairs well with

Rosemary oil Biotin Peptides Niacinamide

Before you start

Topical caffeine is well tolerated. Shampoo contact time is short, so leave-on products deliver more. Persistent or sudden hair loss warrants a dermatologist visit, since proven treatments such as minoxidil exist.

References

Educational, not medical advice. Ingredient guides summarise published research and expert guidance; formulas and concentrations differ between products.