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Common Name(s)

L-tyrosine, tyrosine

Scientific Name(s)


  • How is this product usually used?

      L-tyrosine is usually taken by mouth. It is available in different forms, including capsules, tablets, liquids, and powders.

      As a supplement, L-tyrosine is normally taken as 10 grams once or twice a day, during periods of physical stress or up to one hour in advance.

      Your health care provider may have recommended using this product in other ways. Contact a health care provider if you have questions.

  • What is this product used for?
  • What else should I be aware of?

      L-tyrosine is naturally found in many foods, so it is generally safe when taken in the amounts commonly found in foods.

      Taking L-tyrosine as a supplement may improve alertness and cognitivecognitiverelating to the ability to think, reason, remember, and discern function in physically stressful situations such as sleep deprivation and cold temperatures. Taking L-tyrosine may also improve working memory in a multitasking environment.

      L-tyrosine is generally safe and well tolerated, but should only be used on a short-term, occasional basis. Side effects that have been reported include nausea, fatigue, headache, and heartburn.

      L-tyrosine may reduce the effectiveness of levodopa, a medication used by people with Parkinson's disease, by decreasing its absorption. These 2 medications should be taken at least 2 hours apart.

      If you are following a low-protein diet or are pregnant or are breast-feeding, talk to your doctor before taking L-tyrosine.

      If you take thyroid hormone medications and have hyperthyroidism or Graves' disease, talk to your doctor before taking L-tyrosine. L-tyrosine is a precursor to thyroxine, a type of thyroid hormone, and may increase thyroid hormone levels.

      Before taking any new medications, including natural health products, speak to your physician, pharmacist, or other health care provider. Tell your health care provider about any natural health products you may be taking.

  • Source(s)
      1. Health Canada. Licensed Natural Health Products database. Tyrosine, L-., Accessed June 6, 2016.
      2. L-Tyrosine (monograph). Natural Medicines Comprehensive Database. (Accessed online June 6, 2016).

All material © 1996-2019 MediResource Inc. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

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