L-Tyrosine Review: Nootropic Benefits, Dosage, & Side Effects

Updated on November 19, 2022
 by — reviewed by Jason Williams, PhD (Contributor: George Collins / Editor: Yoko Hill)

In this review, we will take an in-depth look at L-Tyrosine, the benefits of L-Tyrosine, the best dosage, side effects, and reviews from other users on Reddit.

Interested in boosting your brainpower with an amino acid supplement?

L-Tyrosine is a cognitive enhancer that has been shown to improve memory, focus, and mental clarity. It does this by increasing levels of dopamine and norepinephrine, two neurotransmitters that are essential for optimal cognitive function.

If you’re looking for an all-natural way to boost your productivity, L-Tyrosine may be the supplement for you.

It not only supports cognitive function but also helps to maintain a positive mood. This makes it the perfect choice for anyone who wants to stay sharp and focused throughout the day.

But what are the side effects of L-Tyrosine? What is L-Tyrosine used for exactly? And where is the best place to buy L-Tyrosine online?

Let's take a closer look below.

L-Tyrosine Review Summary

L-Tyrosine is an amino acid important for the production of dopamine and norepinephrine, two neurotransmitters critical for cognitive function and mood regulation in humans. L-Tyrosine has been shown to improve mental performance under stress and may also help to protect against age-related cognitive decline conditions such as Parkinson's Disease. The available evidence suggests that L-Tyrosine is safe and well-tolerated.

L-Tyrosine is the perfect nootropic for people who want to improve their mental performance under stress or for those who are concerned about age-related cognitive decline.


  • Helps to improve mental performance under stress
  • Protects against age-related cognitive decline
  • Well-tolerated and considered safe
  • An all-natural nootropic


  • May not be effective for everyone

What Is L-Tyrosine?

L-Tyrosine Review

L-Tyrosine is an amino acid used by the body to produce dopamine and norepinephrine, neurotransmitters that play a role in mood, motivation, focus, and overall cognitive function [1].

Tyrosine is a precursor to these neurotransmitters, meaning that it is required for their production. However, Tyrosine is not directly used by the body to produce dopamine and norepinephrine.

Instead, it must first be converted into L-Tyrosine in order to be used. This conversion occurs inside the brain [2] and is catalyzed by an enzyme called Tyrosine Hydroxylase (TH).

Once L-Tyrosine has been produced, it can then be used by the body to produce dopamine and norepinephrine. Although Tyrosine and L-Tyrosine are similar in structure, they have different roles in the body.

As a result, Tyrosine supplements are sometimes taken in order to improve mood and cognitive function.

How Does L-Tyrosine Work In The Brain?

L-Tyrosine plays a critical role in the formation of catecholamine neurotransmitters, including dopamine, epinephrine, and norepinephrine.

These neurotransmitters are involved in regulating mood, energy levels, and stress response. L-Tyrosine is converted into catecholamines by a two-step process that requires the enzyme Tyrosine Hydroxylase.

First, L-Tyrosine is converted into L-Dopa, which is then further converted into dopamine. Dopamine is then converted into norepinephrine and epinephrine by the enzymes dopamine beta-hydroxylase and phenylethanolamine N-methyltransferase, respectively [3].

This two-step process provides the body with the raw materials necessary to produce all three catecholamine neurotransmitters.

According to Daubner et al., Tyrosine hydroxylase (TH) is the rate-limiting enzyme in the synthesis of dopamine and is thus a key regulator of dopamine levels in the brain.

TH activity is regulated by a number of factors, including catecholamines, GTP, energy levels, and neuronal activity. Catecholamines (e.g. norepinephrine and epinephrine) increase TH activity, while GTP inhibits it.

Energy levels also affect TH activity; when ATP levels are low, TH activity is increased in order to maintain dopamine levels.

Finally, neuronal activity can modulate TH activity; for example, high levels of firing inhibit TH activity, while low levels stimulate it. TH activity is tightly regulated through these mechanisms to ensure appropriate dopamine levels in the brain.

What Is L-Tyrosine Used For?

L-Tyrosine has a wide range of potential uses. For instance, it has been shown to improve mental performance during stressful situations and promotes cognitive flexibility [4].

Additionally, L-Tyrosine is showing promising results as an anti-depressant in multiple animal studies [5].

L-Tyrosine may also be helpful for treating Attention Deficit Hyperactivity Disorder (ADHD). A pilot study showed that when L-Tyrosine was combined with other monoamine amino acids like Tryptophan, 67% of the participants in the study achieved significant symptom reduction [6].

L-Tyrosine has also been shown to stimulate the production of thyroid hormones T3 (triiodothyronine) and T4 (thyroxine). These thyroid hormones play an important role in maintaining both overall physical and cognitive health [7].

There is also some conflicting evidence when it comes to patients who suffer from phenylketonuria (PKU), a genetic disorder that causes an inability to break down the amino acid phenylalanine.

Some studies have shown that L-Tyrosine may help improve cognitive function in those with phenylketonuria, while a recent study from 2013 showed that there is no evidence to suggest that tyrosine should be routinely added to the diet of people with phenylketonuria [8].

What Are The Benefits Of L-Tyrosine For Cognition?

Research suggests that L-Tyrosine is beneficial for overall cognition by improving mental performance during times of stress. Additionally, L-Tyrosine has been shown to improve cognitive performance in people with ADHD [9].

The benefits of L-Tyrosine for cognition can be attributed to its role in the synthesis of dopamine and other catecholamine neurotransmitters.

Dopamine is involved in a wide range of cognitive processes, including attention, motivation, learning, and memory, which explains why L-Tyrosine is a popular supplement in the nootropic community.

Some of the benefits of L-Tyrosine for cognition include:

  • Improving mental performance during stressful situations
  • Promoting cognitive flexibility
  • Improving symptoms of ADHD
  • Stimulating the production of thyroid hormones T3 and T4

Where To Buy L-Tyrosine Online?

If you're looking for a reliable source of L-Tyrosine online, we recommend checking out Pure Nootropics. They offer a high-quality product that is third-party tested for purity and potency. Their L-Tyrosine comes in 90 capsules at 500 mg each at $9.99.

You can get your hands on L-Tyrosine right here:

You can also buy L-Tyrosine from Amazon, although we don't generally recommend buying nootropics from Amazon due to the risk of getting a subpar product.

What Do People Say About L-Tyrosine On Reddit?

Now that we know what L-Tyrosine is and what it's used for, let's take a look at some relevant references and what people are saying about it on Reddit.

"I've been using L-Tyrosine 500mg + 200mg Caffeine before work every day for the past 6 months. I'm a software engineer working in the financial sector. stressful job. I've found that it's really helped me to focus and stay calm under pressure." -/u/zjb22

"I use L-Tyrosine when I know I'll be in a stressful situation or need to be extra alert. It definitely works for me. Better than some pharma medications that tend to increase my blood pressure." -/u/burritomcgee

"I've been using L-Tyrosine for a few weeks now and I'm really impressed. It's helped me to focus and stay motivated throughout the day. Especially on days where I have severe sleep deprivation." -/u/nootroptard

How Do You Take L-Tyrosine For Cognitive Enhancement?

The best way to take L-Tyrosine for cognitive enhancement is to take it on an empty stomach, at least 30 minutes before you need to be cognitively sharp. If you experience any discomfort, you can take it with food as well. If you do that, however, it will take longer for the effects to kick in.

If you're using L-Tyrosine for cognitive enhancement, there's no need to cycle it. You can take it every day, as long as you don't exceed the recommended dosage of 2 grams per day - more on this down below.

Most people split their L-Tyrosine dosage into two doses, taken in the morning and afternoon. This ensures that their levels of L-Tyrosine remain elevated throughout the day for optimal cognitive performance.

What Is The Recommended Dosage For L-Tyrosine?

We recommend starting with a dose of 250 mg and increasing it until you find the sweet spot for you. Some people may need as much as 2,000 mg. However, we don't recommend exceeding 1,000 mg unless you are under the supervision of a qualified medical professional.

A dose between 500-1000 mg is usually the sweet spot for cognitive enhancement.

What Are The Side Effects Of L-Tyrosine?

The side effects of L-Tyrosine are usually mild and include:

  • Headache
  • Insomnia
  • Restlessness
  • Upset stomach
  • Nausea
  • Dizziness
  • Fatigue
  • Irritability
  • Weight loss

The side effects of L-Tyrosine are usually dose-dependent. That is, the higher the dose, the greater the chance of experiencing side effects. If you do experience any side effects, we recommend reducing your dose or discontinuing use altogether and speaking with your doctor or physician.

What Nootropics Are Similar To L-Tyrosine?

The nootropics that are similar to L-Tyrosine are:

  • N-Acetyl L-Tyrosine - This is a more bioavailable form of L-Tyrosine that is easier for the body to absorb and use.
  • DL-Phenylalanine - This amino acid is similar to L-Tyrosine in structure and function. It also has cognitive-enhancing effects and can be used to treat depression.
  • L-Theanine - This amino acid is found in green tea and is known for its calming and relaxing effects. It can also help to enhance cognitive performance and reduce stress.

All of these nootropics are amino acids that have cognitive-enhancing effects. They all work similarly by increasing levels of certain neurotransmitters in the brain (such as dopamine and norepinephrine).

That being said, L-Tyrosine is the best choice for those who want to improve cognitive performance under stress.

What Brain Supplements Can L-Tyrosine Be Stacked With?

L-Tyrosine works incredibly well when it's stacked with a choline source like Alpha GPC or Citicoline. This is because choline increases the synthesis of acetylcholine (ACh), a neurotransmitter essential for cognitive function.

When you stack L-Tyrosine with a choline source, you're essentially giving your brain the raw materials it needs to produce more acetylcholine. This results in enhanced cognitive function, improved memory, and increased focus.

Other nootropics that stack well with L-Tyrosine include:

  • Racetams - Racetams are a class of cognitive-enhancing drugs that work by increasing levels of the neurotransmitter acetylcholine. Adding a racetam to your L-Tyrosine stack can further enhance cognitive function.
  • NooCube - NooCube is a nootropic blend that contains various cognitive-enhancing compounds.

The great thing about NooCube is that it contains both L-Tyrosine and Alpha GPC as well as other nootropic ingredients that work synergistically to enhance cognitive function. No more buying and stacking different nootropics. NooCube has everything you need for optimal cognitive performance in one convenient pill.

If you're looking for a complete and effective nootropic stack, we highly recommend trying NooCube. It's our top-rated brain supplement and comes with a risk-free money-back guarantee, so you have nothing to lose.

Frequently Asked Questions (FAQ)

Here are some frequently asked questions about L-Tyrosine:

Does L-Tyrosine Give You Energy?

L-Tyrosine increases energy levels. This is because l-Tyrosine is an amino acid that directly supports the production of neurotransmitters such as dopamine, a brain chemical known to increase feelings of motivation, excitement, and happiness.

Is L-Tyrosine Good for Anxiety?

L-Tyrosine is a great nootropic for anxiety because it can help to increase levels of dopamine and norepinephrine in the brain. These two neurotransmitters are known to have calming and anti-anxiety effects.

How Long Does It Take For L-Tyrosine To Work?

L-Tyrosine works after 30-60 minutes. This is because it takes time for L-Tyrosine to be absorbed into the bloodstream and transported to the brain, where it can then be used to support the production of neurotransmitters.

How Does L-Tyrosine Make You Feel?

L-Tyrosine gives you a lift in mood, better focus, concentration, and motivation. It also has anti-anxiety effects, which can help to reduce stress levels and overall sense of well-being.

What's The Half-Life Of L-Tyrosine?

L-Tyrosine has a short half-life of 1-2 hours. This means that it takes the body 1-2 hours to break down and eliminate half of the L-Tyrosine that has been consumed.

Is It Safe To Use L-Tyrosine?

L-Tyrosine is a safe, natural nootropic that has been shown to be well-tolerated in human studies. Any side effects are only caused by taking too much and are typically mild and temporary, such as headaches, nausea, and stomach upset.

What Are the Food Sources of L-Tyrosine?

L-Tyrosine is found in many high-protein foods such as meats, poultry, fish, eggs, dairy products, oats, wheat, and beans. The highest concentrations are found in beef and cheese.

What Are the Drug Interactions of L-Tyrosine?

L-Tyrosine interacts with MAO inhibitors and other drugs that increase dopamine levels. It is also important to note that L-Tyrosine supplements should not be taken with SSRI antidepressants (such as Levodopa) as this combination can lead to serotonin syndrome, a potentially life-threatening condition.

What Are the Conditions That L-Tyrosine Is Used For?

L-Tyrosine is used for conditions such as ADHD, anxiety, depression, and stress. It is also sometimes used to boost cognitive function in healthy adults.


L-Tyrosine is a non-essential amino acid that is widely used as a dietary supplement to increase the production of neurotransmitters such as dopamine. It can enhance cognitive function and therefore improve motivation, alertness, mood, and productivity.

L-Tyrosine is GRAS (generally recognized as safe) according to The Food and Drug Administration and considered safe in daily 250 mg to 1000 mg dosages. It is one of the most popular dietary supplements of recent years with little to no negative side effects.

If you're looking for a nootropic that can help to improve cognitive function and increase productivity without having to worry about any harsh side effects, then L-Tyrosine could be the perfect supplement for you.


1Jongkees, Bryant J et al. “Effect of tyrosine supplementation on clinical and healthy populations under stress or cognitive demands--A review.” Journal of psychiatric research vol. 70 (2015): 50-7. doi:10.1016/j.jpsychires.2015.08.014
2Bloemendaal, Mirjam et al. “Neuro-Cognitive Effects of Acute Tyrosine Administration on Reactive and Proactive Response Inhibition in Healthy Older Adults.” eNeuro vol. 5,2 ENEURO.0035-17.2018. 30 Apr. 2018, doi:10.1523/ENEURO.0035-17.2018
3Daubner, S Colette et al. “Tyrosine hydroxylase and regulation of dopamine synthesis.” Archives of biochemistry and biophysics vol. 508,1 (2011): 1-12. doi:10.1016/j.abb.2010.12.017
4Steenbergen, Laura et al. “Tyrosine promotes cognitive flexibility: evidence from proactive vs. reactive control during task switching performance.” Neuropsychologia vol. 69 (2015): 50-5. doi:10.1016/j.neuropsychologia.2015.01.022
5Alabsi, Abdelrahman et al. “The Antidepressant Effect of L-Tyrosine-Loaded Nanoparticles: Behavioral Aspects.” Annals of neurosciences vol. 23,2 (2016): 89-99. doi:10.1159/000443575
6Hinz, Marty et al. “Treatment of attention deficit hyperactivity disorder with monoamine amino acid precursors and organic cation transporter assay interpretation.” Neuropsychiatric disease and treatment vol. 7 31-8. 26 Jan. 2011, doi:10.2147/NDT.S16270
7National Center for Biotechnology Information. (n.d.). Retrieved July 17, 2022, from https://www.ncbi.nlm.nih.gov/books/NBK285550/
8Webster, Diana, and Joanne Wildgoose. “Tyrosine supplementation for phenylketonuria.” The Cochrane database of systematic reviews vol. 2013,6 CD001507. 5 Jun. 2013, doi:10.1002/14651858.CD001507.pub3
9Ahn, James et al. “Natural Product-Derived Treatments for Attention-Deficit/Hyperactivity Disorder: Safety, Efficacy, and Therapeutic Potential of Combination Therapy.” Neural plasticity vol. 2016 (2016): 1320423. doi:10.1155/2016/1320423