L-Tyrosine
Commonly used for
Focus
Where to Buy
Our experts personally review each product we recommend for quality and cost effectiveness.
The cheapest product is usually low quality, but more expensive doesn’t always mean better.
The cheapest product is usually low quality, but more expensive doesn’t always mean better.
What is it? / Overview
Tyrosine is the amino acid precursor to dopamine and norepinephrine, and supplementation may help preserve cognitive performance specifically during acute stress, sleep loss, or multitasking, when catecholamine stores can become depleted.
How is it used? / Administration
Form: L-Tyrosine — the form with the stronger human evidence base; N-Acetyl-L-Tyrosine (NALT) is sometimes marketed as an alternative but shouldn't be assumed equivalent or preferred.
Typical dose studied: 500–2,000 mg, taken 30–60 minutes before a demanding task
Timing: On an empty stomach, 30–60 minutes before a stressful or demanding cognitive task
Benefit is most consistent under acute stress/fatigue conditions specifically, not as a general everyday cognitive enhancer. Avoid combining with MAOIs due to hypertensive crisis risk.
How well does it work? / Evidence
~ Moderate evidence
Who should avoid it?
Avoid with: Hyperthyroidism / Graves disease
Interacts with: Thyroid medications; MAOIs (Monoamine oxidase inhibitors)
Already taking it? Most beneficial specifically under acute stress, sleep deprivation, or multitasking demands — not established as a general athletic-performance or everyday-energy supplement.
Research & references
Jongkees BJ et al. Tyrosine and cognitive control under stress. Attipoe S et al. Tyrosine for cognitive/physical performance under stress — review.
Disclosure: Knozela is a participant in the Amazon Associates affiliate program. Some "Where to buy" links on this page are affiliate links -- if you make a purchase through them, Knozela may earn a commission at no additional cost to you.