L-Tyrosine

L-Tyrosine is an amino acid, which is a building block of protein that your body makes naturally. You can also find L-Tyrosine in some foods like meat, fish, eggs, dairy products, beans, nuts, oats, and wheat.

Some people have low levels of L-Tyrosine because of a genetic condition called phenylketonuria (PKU). In individuals with PKU, the body cannot process an amino acid called phenylalanine, which is needed to make L-Tyrosine.

L-Tyrosine is given as a supplement to raise L-Tyrosine levels in people with PKU.

L-Tyrosine has been used in alternative medicine as a possibly helpful way to improve mental performance, alertness, or memory.

L-Tyrosine has also been used to treat depression or attention deficit disorder (ADD or ADHD). However, studies have shown that L-Tyrosine may not be effective for these conditions. L-Tyrosine may also not improve exercise performance.

Other uses that have not been proven by research include dementia, high blood pressure, narcolepsy, schizophrenia, weight loss, premenstrual syndrome, Parkinson's disease, chronic fatigue syndrome, alcoholism, cocaine addiction, and other conditions.

It is not clear if L-Tyrosine is effective for treating any medical condition. The FDA has not approved the medicinal use of this product. L-Tyrosine should not be used instead of medication prescribed by your doctor.

L-Tyrosine is often sold as an herbal supplement. Many herbal compounds do not have regulated manufacturing standards, and some supplements on the market have been found to be contaminated with toxic metals or other drugs. It is important to buy herbal/health supplements from a trustworthy source to reduce the risk of contamination.

L-Tyrosine may also be used for purposes not listed in this product guide.

When thinking about using herbal supplements, talk to your doctor. You might also want to consult someone who is trained in herbal/health supplements.

If you decide to take L-Tyrosine, use it as instructed on the package or as directed by your doctor, pharmacist, or other healthcare provider. Do not take more of this product than what is recommended on the label.

Your dose of L-Tyrosine will depend on how much protein you eat in your diet. Follow your doctor's dosing instructions very carefully.

L-Tyrosine is just one part of a complete treatment plan that may also include a special diet. Follow the diet plan that your doctor or nutrition counselor has created for you. Make sure you know which foods you need to eat or avoid to help manage your condition.

Contact your doctor if the condition you are treating with L-Tyrosine does not get better, or if it worsens while using this product.

Store at room temperature, away from moisture and heat.

Follow all the instructions on the product label and package. Inform each of your healthcare providers about all your medical conditions, allergies, and all medications you are taking.

Before using L-Tyrosine, talk to your healthcare provider. You may not be able to use L-Tyrosine if you have certain medical conditions, especially:

• overactive thyroid; or
• Graves disease.

It is not known whether L-Tyrosine will harm an unborn baby. Do not use this product without medical advice if you are pregnant.

It is not known whether tyrosine passes into breast milk or if it could harm a nursing baby. Do not use this product without medical advice if you are breast-feeding a baby.

Do not give any herbal/health supplement to a child without medical advice.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Although not all side effects are known, L-Tyrosine is thought to be likely safe in most adults when taken for up to 3 months.

Common side effects of L-Tyrosine may include:

• nausea, heartburn;
• headache;
• joint pain; or
• feeling tired.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Skip the missed dose if it is nearly time for your next scheduled dose. Do not use extra L-Tyrosine to compensate for the missed dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Follow your healthcare provider's instructions regarding any restrictions on food, drinks, or activities.

Do not take L-Tyrosine without medical advice if you are using any of the following medications:

• levodopa; or
• thyroid replacement (Synthroid, Levothroid, and others).

This list is not complete. Other drugs may interact with tyrosine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this product guide.