L-
tyrosine (also known just as tyrosine) is a nonessential amino acid. This means that it does not need to be obtained from dietary sources; the human body can make L-tyrosine using
phenylalanine, another amino acid. It is also used in
dietary supplements and is claimed to be useful for a variety of different conditions, such as:
- Depression
- Premenstrual syndrome (PMS)
- Attention deficit hyperactivity disorder (ADHD).
As mentioned, L-tyrosine is an amino acid that is important for building proteins. For most people, the body can make its own, although it is also found in protein-rich foods. People with phenylketonuria (PKU) must obtain L-tyrosine through the diet, since they cannot produce it. Even though it is a large amino acid, L-tyrosine can cross the blood-brain barrier to enter the brain, and may have numerous different effects in the brain. It is not known how this product may work for a variety of different disorders.
L-tyrosine (as part of a specially designed protein supplement) is effective for people with phenylketonuria, although further supplementation in addition to the protein supplement is usually not recommended.
It is not known if it is effective for other uses.
A safe and effective L-
tyrosine dose has not yet been established. Be sure to follow the specific instructions on your particular product.
Side Effects of L-Tyrosine
Although it is a "natural" product, L-tyrosine can still cause side effects. Some of the more commonly reported side effects include:
(Click L-Tyrosine Side Effects to learn more, including potentially serious side effects you should report immediately to your healthcare provider.)
Some people may be more likely than others to experience problems with L-tyrosine. Therefore, you should talk with your healthcare provider before taking it if you have:
- Hyperthyroidism (an overactive thyroid)
- Graves' disease
- Phenylketonuria (PKU)
- Any allergies, including allergies to food, dyes, or preservatives.
Also, let your healthcare provider know if you are:
Make sure to tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.
(Click L-Tyrosine Safety for more information, including any available warnings and precautions.)
What If I Take an Overdose?
It is not known what exactly to expect from an L-
tyrosine overdose. If you think you may have taken too much, seek immediate medical attention.
How Should L-Tyrosine Be Stored?
Refer to the label of your individual product for information on how best to store it. Keep L-tyrosine and all other medications and supplements out of the reach of children.
