Can L-Tyrosine Help With ADHD Symptoms?

Woman reading a supplement bottle.

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What Is L-Tyrosine?

L-tyrosine is an amino acid that is a precursor (which means it’s necessary for production) to dopamine and norepinephrine, two neurotransmitters that are important for focus and concentration.

L-tyrosine has been shown to help improve cognitive performance during times of stress and improve working memory.

Because of this, it is believed that L-tyrosine may help with attention deficit hyperactivity disorder (ADHD) symptoms. However, there is limited research on the effectiveness of L-tyrosine for ADHD, and more studies are needed to confirm its efficacy. If you're considering using L-tyrosine for ADHD, talk to your doctor first to see if it's right for you.

Can L-Tyrosine Help With ADHD Symptoms?

There is some evidence that L-tyrosine may help with attention deficit hyperactivity disorder (ADHD) symptoms. A small study found that L-tyrosine improved task performance in people with ADHD during a laboratory test of working memory.

However, it’s unclear if L-tyrosine would have the same effect in real-world settings. Additionally, more research is needed to confirm these findings.

Where to Find L-Tyrosine

L-tyrosine is an amino acid that’s a precursor to dopamine and norepinephrine. These neurotransmitters play an important role in focus and concentration. L-tyrosine is found naturally in many foods, including the following:

  • Eggs
  • Fish
  • Meat
  • Milk
  • Tofu
  • Beans
  • Seeds

L-tyrosine is also available in supplement form. It’s sometimes combined with other ingredients, such as:

  • Vitamins B6 and B12: for converting L-tyrosine to dopamine
  • Acetyl-L-carnitine: for improving mental clarity
  • Folic acid: for reducing symptoms of depression

How Does L-Tyrosine Work?

Dopamine and norepinephrine are important neurotransmitters that play a role in focus and concentration. They’re also involved in the “reward center” of the brain, which helps regulate motivation and pleasure.

L-tyrosine is a precursor to these neurotransmitters. By supplementing with L-tyrosine, you may be able to increase levels of dopamine and norepinephrine and improve focus and concentration.

Is L-Tyrosine the Same as Adderall?

L-tyrosine is often compared to Adderall, a medication used to treat ADHD. Both L-tyrosine and Adderall can improve task performance in people with ADHD. However, they work in different ways.

Adderall vs. L-tyrosine

Adderall is a stimulant that increases levels of the neurotransmitters dopamine and norepinephrine in the brain. In contrast, L-tyrosine is thought to increase levels of dopamine and norepinephrine by providing the building blocks needed to make these neurotransmitters.

How to Take L-Tyrosine

You can find L-tyrosine supplements at most health food stores. The usual dose is 500 mg to 2 grams per day. If you have ADHD, it’s best to start with a lower dose and increase it gradually as needed.

You should also talk to your doctor before taking L-tyrosine or any other supplement, especially if you have a health condition or are taking other medications.

Possible Side Effects

L-tyrosine is generally considered safe when taken in recommended doses. However, it can cause some side effects, such as the following:

  • Anxiety
  • Headache
  • High blood pressure
  • Insomnia
  • Nausea
  • Restlessness
  • Skin flushing
  • Stomach upset
  • Vomiting

If you have ADHD, you may be more sensitive to the side effects of L-tyrosine. Therefore, it’s important to start with a lower dose and increase gradually as needed. If you experience any side effects, stop taking the supplement and talk to your doctor.

What Chemical Are You Lacking If You Have ADHD?

There is no one “chemical” that people with ADHD are lacking. However, some research suggests that ADHD may be associated with a deficiency in the neurotransmitters dopamine and norepinephrine.

L-tyrosine is thought to increase levels of dopamine and norepinephrine by providing the building blocks needed to make these neurotransmitters. Therefore, L-tyrosine may help improve symptoms of ADHD.

How Long Does It Take for L-Tyrosine to Work?

The effects of L-tyrosine may not be immediate. It may take several weeks for you to notice any changes in your symptoms. If you don’t notice any improvement after a few weeks, you may want to try a higher dose or talk to your doctor about other treatment options.

What Are the Benefits of L-Tyrosine?

As a dietary supplement, L-tyrosine has been used for the following:

  • Improving mental clarity
  • Supporting healthy brain function
  • Reducing stress
  • Increasing energy levels
  • Heightening alertness
  • Promoting weight loss
  • Improving athletic performance
  • Lowering blood pressure
  • Reducing symptoms of depression

Some of these claims are supported by science, while others are not. Let’s take a closer look at some of the science-backed benefits of L-tyrosine.

Mental Clarity

L-tyrosine is thought to improve mental clarity by increasing levels of the neurotransmitters dopamine and norepinephrine.

In one study, healthy adults were given either L-tyrosine or a placebo before completing a task that required switching from one thing to another.

Those who took L-tyrosine demonstrated more cognitive flexibility than those who took the placebo.

Stress Tolerance

A review of studies found that L-tyrosine may help improve mental performance during times of stress.

For example, L-tyrosine has been shown to improve mental performance in healthy adults who were exposed to cold temperatures.

Reducing Anxiety

L-tyrosine may also help reduce symptoms of anxiety. One study found that L-tyrosine reduced stress and increased feelings of relaxation in healthy adults.

Who Should Not Take L-Tyrosine?

L-tyrosine is generally considered safe when taken at recommended doses. However, it can cause side effects and can also interact with some medications. Therefore, it’s important to talk to your doctor before taking L-tyrosine or any other supplement. If you have an underlying health condition or are taking medications, it is especially important to speak to your doctor before taking L-tyrosine.

A Word From Verywell

There is some evidence that L-tyrosine may help with attention deficit hyperactivity disorder (ADHD) symptoms. However, more research is needed to confirm these findings. If you’re considering taking L-tyrosine for ADHD, talk to your doctor first. They can help you weigh the potential risks and benefits and determine if L-tyrosine is right for you.

13 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Jongkees BJ, Hommel B, Kühn S, Colzato LS. Effect of tyrosine supplementation on clinical and healthy populations under stress or cognitive demands--A reviewJ Psychiatr Res. 2015;70:50-57. doi:10.1016/j.jpsychires.2015.08.014

  2. Colzato LS, Steenbergen L, Sellaro R, Stock AK, Arning L, Beste C. Effects of l-Tyrosine on working memory and inhibitory control are determined by DRD2 genotypes: A randomized controlled trialCortex. 2016;82:217-224. doi:10.1016/j.cortex.2016.06.010

  3. US Department of Agriculture. Eggs, Grade A, Large, egg white.

  4. Guilarte TR. Effect of vitamin B-6 nutrition on the levels of dopamine, dopamine metabolites, dopa decarboxylase activity, tyrosine, and GABA in the developing rat corpus striatumNeurochem Res. 1989;14(6):571-578. doi:10.1007/BF00964920

  5. Traina G. The neurobiology of acetyl-L-carnitineFront Biosci (Landmark Ed). 2016;21(7):1314-1329. Published 2016 Jun 1. doi:10.2741/4459

  6. Popa TA, Ladea M. Nutrition and depression at the forefront of progressJ Med Life. 2012;5(4):414-419.

  7. FDA. Adderall Medication Guide.

  8. Young SN. L-tyrosine to alleviate the effects of stress?J Psychiatry Neurosci. 2007;32(3):224.

  9. National Library of Medicine. Tyrosine.

  10. Gold MS, Blum K, Oscar-Berman M, Braverman ER. Low dopamine function in attention deficit/hyperactivity disorder: should genotyping signify early diagnosis in children?Postgrad Med. 2014;126(1):153-177. doi:10.3810/pgm.2014.01.2735

  11. Alabsi A, Khoudary AC, Abdelwahed W. The Antidepressant Effect of L-Tyrosine-Loaded Nanoparticles: Behavioral Aspects [published correction appears in Ann Neurosci. 2019 Jan;25(3):141-151]. Ann Neurosci. 2016;23(2):89-99. doi:10.1159/000443575

  12. Steenbergen L, Sellaro R, Hommel B, Colzato LS. Tyrosine promotes cognitive flexibility: evidence from proactive vs. reactive control during task switching performanceNeuropsychologia. 2015;69:50-55. doi:10.1016/j.neuropsychologia.2015.01.022

  13. Shurtleff D, Thomas JR, Schrot J, Kowalski K, Harford R. Tyrosine reverses a cold-induced working memory deficit in humansPharmacol Biochem Behav. 1994;47(4):935-941. doi:10.1016/0091-3057(94)90299-2

By Arlin Cuncic
Arlin Cuncic, MA, is the author of "Therapy in Focus: What to Expect from CBT for Social Anxiety Disorder" and "7 Weeks to Reduce Anxiety."