Ingredient guide · cognitive

L-Tyrosine

Dopamine precursor for focus under stress

The clinically studied dose

1g per day Studied

Source: Examine.com — Tyrosine — 500–2,000 mg (or ~100–150 mg/kg) before acute stress to protect cognition.

Acute stress/cognition studies use far more (≈100–150 mg/kg); 1 g is a practical everyday target (500 mg is on the light side).

What it is

An amino acid that's the raw material for dopamine and adrenaline.

What the research supports

How it works

Replenishes catecholamine neurotransmitters that get depleted during stress.

Human evidence

Tyrosine prevented cognitive decline under stress, cold, or sleep deprivation — but did little in rested, unstressed conditions.

Systematic review of RCTs · n=15 studies · ~100–150 mg/kg — Jongkees et al., 2015 — J Psychiatr Res (review)

After overnight sleep deprivation, tyrosine restored alertness and working memory versus placebo for several hours.

Double-blind crossover RCT · n=20 · 150 mg/kg — Neri et al., 1995 — Aviat Space Environ Med

Bottom line: Works specifically as a 'stress buffer' — it helps thinking under sleep deprivation, cold, or heavy multitasking, but does little when you're rested and calm. It's not a daily focus pill.

Side effects & safety

Safe for most. Avoid with thyroid medication or MAOI antidepressants. Works best acutely before a stressor, not as a daily mood-lifter.

What users report COMMUNITY · ANECDOTAL

Polarizing
Distilled from 7 top threads across r/Nootropics & r/StackAdvice (280 comments) on r/Nootropics · read the threads yourself →
✓ Reported benefits
commonA clutch focus aid for ADHD / stimulant users — several say it restores blunted Adderall or Vyvanse
common1–2 g rescues focus after a poor night's sleep
⚠ Reported downsides
notedSome get depressed for days, or feel sleepy, edgy, or anxious on it
commonFast tolerance — 'worked the first week, then faded'; some can only dose once a week
🤨 The skeptic take
strong consensusThe science-literate refrain: it's not the rate-limiting step — does little unless you're protein-deficient or on stimulants
recurringTake on an empty stomach, away from protein, or it won't absorb

Anecdotes, not evidence, and not medical advice. Frequency labels are our read of forum sentiment, not a formal survey. Individual responses vary widely.

What it should cost

Per serving
Typical branded single-ingredient product$0.42
Bulk powder at the clinical dose (500g, $24.97)$0.05

Buying bulk powder instead of a branded bottle saves about 88% per serving.

Bulk price: $24.97/500g → Alt source: $9.99/250g

Graded products that contain it

Related ingredients

Educational only — not medical advice. Grades and clinical doses are computed from public labels against sourced research (citations on the main site); prices last verified 2026-07-21. Expensive Powder has no sponsors; bulk links may earn an affiliate commission, which never affects a grade. Talk to a clinician before starting any supplement.