What are nootropics? The definition, the categories, and what counts

01The short version

A nootropic is any substance taken to improve a mental function such as attention, memory, learning or motivation. The word covers everything from a cup of coffee to a prescription stimulant, which is why it has become almost meaningless in marketing. This guide gives you the original definition, the honest categories, and a way to tell whether something deserves the label.

02Where the word came from

The term was coined in 1972 by Corneliu Giurgea, the Romanian chemist who synthesised piracetam. He set out five conditions for a true nootropic: it should enhance learning and memory, protect the brain against disruption, protect against physical or chemical injury, improve the brain's control mechanisms, and have very few side effects and almost no toxicity. By that standard caffeine fails on the last point, most prescription stimulants fail on several, and very few compounds pass at all.

Modern usage has dropped the strict conditions and kept the idea: something you take to think better.

03The categories

Everyday stimulants

Caffeine, and caffeine paired with L-theanine. The best-evidenced, cheapest and most widely used nootropic on earth. Also the one with the clearest tolerance and crash.

Plant extracts and "adaptogens"

Bacopa, Rhodiola, Ginkgo, Lion's Mane, Ashwagandha. Evidence ranges from moderate (Bacopa for memory over months) to thin (Lion's Mane in humans). Effects are slow and small.

Nutrients

Creatine, omega-3, B vitamins, magnesium. Useful if you are deficient, modest otherwise. Creatine has surprisingly good data for cognition in sleep-deprived and vegetarian adults.

Synthetic compounds

Racetams, Noopept, and the Russian peptides Semax and Selank. Designed molecules with specific mechanisms and, in Semax's case, a controlled human study in healthy adults [1]. This is where the interesting evidence sits, and also where the quality of what you buy matters most.

Prescription drugs used off-label

Modafinil, methylphenidate, amphetamine. Effective, controlled, and not what this site is about.

04Do nootropics work?

Some do, for some things, by a measurable amount. Caffeine improves alertness and reaction time reliably. Creatine improves working memory in people who are short of it. Semax improved attention and short-term memory scores in a controlled trial, with the effect lasting most of a day [1]. Most of the rest have effects that are either small, slow, or only shown in animals. The honest way to read the field is: a few real tools, a lot of noise, and a marketing industry built on the noise.

05Are nootropics safe, and are they legal in the UK?

Caffeine, plant extracts and nutrients are food supplements and freely sold. Racetams and peptides such as Semax are not licensed medicines but are not controlled either; they occupy a grey area explained in Is Semax legal in the UK?. Prescription stimulants are controlled and possessing them without a prescription is an offence.

Safety follows the same order. Anything with a long human track record and a known dose is low risk for a healthy adult. Anything sold as a research chemical with no certificate is a risk regardless of what the molecule is supposed to be, which is why we publish a batch assay for every lot.

06How to tell if something deserves the name

• One named active, at a stated dose. Blends with "proprietary" amounts are hiding something.
• At least one human study, ideally in people like you, ideally measuring the thing you want.
• A mechanism that makes sense and does not depend on a stimulant.
• A certificate of analysis you can read.

Our own ranking against those criteria is in the best nootropics in the UK.