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Other name(s):

a-amino-b-[p-hydroxyphenyl]-propionic acid

General description and uses

Tyrosine is an amino acid (protein-building block) that the body synthesizes from phenylalanine. This is another amino acid. It helps make neurotransmitters, such as dopamine, norepinephrine, and epinephrine. It helps make thyroid hormones, such as thyroxine. It also helps make melanin. This is the pigment responsible for hair and skin color. Amino acids are available as single amino acids or in amino-acid combinations. They also come as part of multivitamins, proteins, and food supplements. The forms include tablets, fluids, and powders.

You should get all the amino acids you need by eating enough protein in your diet.

People with phenylketonuria may need to take tyrosine supplements. Or medicines that are able to help turn phenylalanine into tyrosine. 

Unproven claims

There may be benefits that have not yet been proven through research.

Tyrosine is said to improve mood. It may help treat depression, anxiety, narcolepsy, and insomnia. It may help suppress appetite and reduce body fat. It may prompt the release of human growth hormone. It’s been used to treat some allergies.

Side effects, toxicity, and interactions

Using a single amino acid supplement may lead to negative nitrogen balance. This can reduce how well your metabolism works. It can make your kidneys work harder. In children, single amino acid supplements may cause growth problems.

You should not take high doses of single amino acids for long periods of time.

You should not use this supplement if:

  • You have melanoma (pigmented type)

  • You have tyrosinemia type I or II

  • You take a monoamine oxidase inhibitor to treat depression

  • You are pregnant or breastfeeding

Talk with your healthcare provider before taking tyrosine supplements if you have an overactive thyroid (hyperthyroid). 

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