L-Tyrosine

• improves focus, performance, and memory in times of acute stress
• improves mental clarity and attention
• increases dopamine levels 

L-Tyrosine is an amino acid found in the diet that is metabolized to produce catecholamines such as dopamine and adrenaline.

Dosage: 
Anecdotally, L-Tyrosine tends to be taken in doses of 500-2000mg approximately 30-60 minutes before any acute stressor

"L-Tyrosine," Examine.com, published on 22 June 2013, last updated on 13 September 2021, https://examine.com/supplements/l-tyrosine/