Tyrosine (C9H11NO3) is most commonly used in protein supplements to treat an inherited disorder called phenylketonuria (PKU). People who have this disorder can’t process phenylalanine properly. As a result they can’t make tyrosine. To meet their bodies’ needs, supplemental tyrosine is given.
Tyrosine is also commonly used to improve learning, memory, and alertness, especially during stressful situations.
The body uses tyrosine to make chemical messengers that are involved in conditions involving the brain such as mental alertness.