Tyrosine is most commonly used in protein supplements for an inherited disorder called phenylketonuria (PKU). It is also used for alcoholism, cocaine dependence, and memory and thinking skills, but there is no good scientific evidence to support these uses.
How does it work ?
Uses & Effectiveness
- An inherited disorder that increases levels of phenylalanine in the blood (phenylketonuria or PKU). People with PKU are not able to process the amino acid phenylalanine. This amino acid is used by the body to make tyrosine. Because of this, people with PKU can have low levels of tyrosine in the body. To prevent tyrosine levels from becoming too low, people with PKU are advised to consume medical foods containing tyrosine but very little phenylalanine. Tyrosine levels in the blood are regularly measured by physicians.
Possibly Effective for
- Memory and thinking skills (cognitive function). Research shows that taking tyrosine might improve mental performance, usually under stressful conditions These include cold-induced stress or noise-induced stress.
- Memory. Research shows that taking tyrosine improves memory during stressful conditions. These include cold-induced stress or multi-tasking. Tyrosine does not seem to improve memory during less stressful situations.
Possibly Ineffective for
- Athletic performance. Taking tyrosine before running or cycling does not seem to improve strength, stamina, or performance.
Insufficient Evidence for
- Attention deficit-hyperactivity disorder (ADHD). Taking tyrosine by mouth does not seem to improve symptoms in children or adults with ADHD.
- Depression. Early research suggests that taking tyrosine does not improve symptoms of depression.
- High blood pressure. Early research shows that taking tyrosine by mouth does not reduce blood pressure in people with slightly high blood pressure.
- Excessive daytime sleepiness (narcolepsy). Research shows that taking tyrosine by mouth might reduce some symptoms of narcolepsy, such as feelings of tiredness. But it does not seem to improve most symptoms based on clinical assessment.
- Schizophrenia. Early research shows that taking tyrosine along with the drug therapy does not further improve symptoms of schizophrenia.
- Lack of sleep (sleep deprivation). Early research shows that tyrosine might help people who have lost a night's sleep to stay alert. It might also improve their memory and reasoning.
- Alcohol use disorder.
- Alzheimer disease.
- Cocaine use disorder.
- Diseases, such as Alzheimer disease, that interfere with thinking (dementia).
- Erectile dysfunction (ED).
- A group of disorders that most often cause muscle weakness (mitochondrial myopathies).
- Parkinson disease.
- Premenstrual syndrome (PMS).
- Skinwrinkles from sun damage.
- Other conditions.
When applied to the skin: Tyrosine is POSSIBLY SAFE when applied to the skin.
Special Precautions and Warnings
Thyroid disorders: The body uses tyrosine to make thyroxine, a thyroid hormone. Taking extra tyrosine might increase thyroxine levels too much. This could make hyperthyroidism and Graves disease worse. If you have a thyroid disorder, don't take tyrosine supplements.
Levodopa interacts with TYROSINE
Tyrosine might decrease how much levodopa the body absorbs. By decreasing how much levodopa the body absorbs, tyrosine might decrease the effectiveness of levodopa. Do not take tyrosine and levodopa at the same time.
Thyroid hormone interacts with TYROSINE
The body naturally produces thyroid hormones. Tyrosine might increase how much thyroid hormone the body produces. Taking tyrosine with thyroid hormone pills might cause there to be too much thyroid hormone. This could increase the effects and side effects of thyroid hormones.
Be cautious with this combination
- For memory and thinking skills (cognitive function): A single dose of 100-300 mg/kg or 2 grams of tyrosine has been taken before a stressful mental task.
- For memory: 150-300 mg/kg of tyrosine has been used before a memory task.
- For an inherited disorder that increases levels of phenylalanine in the blood (phenylketonuria or PKU): Foods and medical foods providing 4-6 grams of tyrosine daily are recommended. Women with PKU who are pregnant or breastfeeding are advised to consume foods providing 6-7.6 grams of tyrosine daily. A doctor will measure tyrosine levels in the blood to make sure they don't become too high or too low. For most people with PKU, additional separate supplementation with free tyrosine is not recommended. It can cause wide variations in the amount of tyrosine in the blood. This could cause unwanted side effects.
- For an inherited disorder that increases levels of phenylalanine in the blood (phenylketonuria or PKU): Foods and medical foods providing tyrosine 1.1-6.0 grams daily, depending on age, are recommended from infancy. A doctor will measure tyrosine levels in the blood to make sure they don't become too high or too low. For most people with PKU, additional separate supplementation with free tyrosine is not recommended. It can cause wide variations in the amount of tyrosine in the blood. This could cause unwanted side effects.
CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.
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