Caffeine Lube, Caffeine Shampoo

Pjur Espresso is a lube which contains a small amount of caffeine. It’s doubtful you would absorb enough caffeine from it through your skin or mucous membranes to feel the typical effects of ingesting caffeine (and reports say that it’s especially bitter-tasting, if you’re planning on chugging it.) Like most non-edible caffeinated products, it doesn’t do what you’re hoping it would do, and is both more expensive and less pleasant than drinking a coffee or a soda.

I did find one topical caffeine product, though, which has scientifically-proven data to back up its claims: caffeine shampoo can induce a small increase in hair growth, per an article in the British Journal of Dermatology. So Alpecin Shampoo, which contains 5000mg of caffeine in its tiny 250mL (approx 8-fl. oz) bottles, can blast your hair follicles with an enormous dose of caffeine without very much of it entering your bloodstream. The average cup of coffee contains 100-150mg of caffeine, which means that if a significant amount of it DID enter your bloodstream through your scalp, you’d suffer an acute caffeine overdose from using Alpecin.

This is the same reason why caffeinated soap doesn’t work very well (here’s my previous writeup, if you’re curious as to how much caffeine you actually absorb through your skin, and how long it takes.)