ADHD and L-Theanine: Benefits, Uses, and Risks

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Disclaimer: None of what is published on is intended to be professional medical advice. Consult your health practitioner regarding any medical treatment or diagnosis.

If you, or someone close to you are living with ADHD, you might be actively searching for effective ways to manage the symptoms. According to limited research and anecdotal reports, L-theanine, an amino acid most commonly found in green and black tea, could be a natural treatment worth exploring. 

Let's dive into the benefits, uses, and potential risks of using L-theanine for ADHD. 

Key Takeaways

  • Limited studies suggest that L-theanine may be a helpful supplement in managing ADHD symptoms.
  • L-theanine has calming, focusing, and stress-relieving effects.
  • There’s no one-size-fits-all for dosing L-theanine for ADHD, so it’s important to increase dosage to find what’s best for you gradually.

What is ADHD?

ADHD, or attention-deficit hyperactivity disorder, is a neurodevelopmental disorder that most often affects children but can also occur in adults. Common symptoms include difficulty focusing, impulsiveness, and hyperactivity. This can be a challenge in everyday life and routines, affecting performance at school, work, and even relationships.  

Traditional treatments for ADHD include a variety of FDA-approved medications, behavioral therapy, or a combination of the two.

What is L-Theanine?

L-theanine is a naturally occurring amino acid commonly found in tea leaves, particularly green tea. It is known for its calming and relaxing effects on the mind and body. 

L-Theanine was first discovered as a component in green tea in the mid-20th century. The compound is present in green, black, and white tea, as well as in certain varieties of fungi. A typical cup of tea contains about 20 mg of L-theanine, while most L-theanine supplements contain 50-250mg per serving.

Since its discovery, L-theanine has risen in popularity for its remarkable range of wellness uses, and a body of scientific studies has emerged to support these claims. It’s used for stress management, improving mood, heightening focus and concentration, as a sleep aid, and even for mitigating cravings for other substances. So how does it work?

Research shows us that L-theanine is structurally similar to glutamate, an essential neurotransmitter in the brain, and it can cross the blood-brain barrier, allowing it to affect brain function directly. It also appears to increase the amount and effectiveness of GABA and dopamine in the brain. Higher levels of GABA correlate with calmer mental states and decreased anxiety.

Some studies also indicate that L-theanine works on alpha brain waves, increasing their frequency. Heightened alpha wave activity in the brain is associated with calmer, more focused states – they’re often found in the brain activity of Zen meditation masters. 

Research is still uncovering other potential mechanisms by which L-theanine works and its potential benefits. Still, the current state of science is encouraging enough for those interested in trying it as a supplement.

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Potential Benefits of ADHD and L-Theanine

Traditional ADHD treatments, such as medication, can be effective, but their success is far from universal. L-theanine’s various mechanisms and calming, focusing effects offer a natural alternative or supplement to typical ADHD treatment plans.

One of L-theanine’s main benefits is its ability to promote relaxation and reduce anxiety. Symptoms of anxiety and stress often accompany ADHD, and L-theanine use may contribute to better focus and attention in individuals with ADHD. 

L-theanine’s impact on cognitive function can also help produce a more relaxed state of alertness, improving mental clarity and focus in those who struggle to manage their symptoms. One study showed that L-theanine significantly enhanced focus and attention in boys with ADHD compared to caffeine or a placebo.

Individuals with ADHD also typically have issues with falling asleep, distracted by wayward thoughts around bedtime. A review examining ADHD and sleep disturbance suggested that L-theanine might improve sleep efficiency in those with the condition. L-theanine’s calming effects may help promote overall relaxation and enhance sleep quality, assisting individuals in getting better rest and overall managing their day-to-day lives. 

Potential Risks and Side Effects

While L-theanine is generally considered safe for most people, it is essential to be aware of potential risks or side effects when using it for ADHD. 

Some individuals may experience mild gastrointestinal symptoms such as stomach upset, nausea, or diarrhea. These symptoms are usually temporary and subside quickly, but if you experience persistent or severe gastrointestinal issues, discontinue use and consult a healthcare professional.

It’s important to remember that research on L-theanine has not been exhaustive. Researchers don’t know all its potential side effects or drug interactions, so it’s essential to discuss with your doctor if you’re concerned about current medications.

It is also key to remember that L-theanine is not a substitute for prescribed ADHD medications. While it may benefit those seeking to manage symptoms, it should not be a standalone treatment. 

How to Use L-Theanine for ADHD

The amount of L-theanine one should take for ADHD depends on many factors, including age, weight, and severity of symptoms. There’s no standardized dose for the compound, so individuals will need to experiment for desired outcomes.

One of the studies above that explored L-theanine used approximately 2.5 mg per kilogram of body weight for children. Another adult study gave participants 200 mg of L-theanine per dose. These doses may be helpful, but it’s best to start with lower amounts and gradually increase to observe your response.

Combining L-theanine with caffeine may also produce complementary beneficial effects, such as in a cup of green tea. One study observed that L-theanine reduced the jitters and anxiety associated with caffeine consumption while retaining the focusing effects, which may help soothe the anxiety associated with ADHD.

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The Bottom Line: Should You Take L-Theanine for ADHD?

Early studies indicate L-theanine has promising potential as a natural supplement for managing ADHD symptoms. Its ability to promote relaxation, improve focus, and reduce anxiety makes it a valuable supplement to the treatment plan for individuals with ADHD. 

However, it is essential to note that L-theanine should not be considered a standalone treatment for ADHD but rather as a complementary approach alongside other recommended interventions. It is always advisable to consult with a healthcare professional before starting any new supplement regimen.


  1. Hidese, S., Ogawa, S., Ota, M., Ishida, I., Yasukawa, Z., Ozeki, M., & Kunugi, H. (2019). Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial. Nutrients, 11(10).
  2. Kimura, K., Ozeki, M., Juneja, L. R., & Ohira, H. (2007). L-Theanine reduces psychological and physiological stress responses. Biological Psychology, 74(1), 39-45.
  3. Nobre AC, Rao A, Owen GN. L-theanine, a natural constituent in tea, and its effect on mental state. Asia Pac J Clin Nutr. 2008;17 Suppl 1:167-8. PMID: 18296328.
  4. Kahathuduwa, C., Wakefield, S., West, B., Blume, J., & Mastergeorge, A. (2019). L-theanine and Caffeine Improve Sustained Attention, Impulsivity and Cognition in Children with Attention Deficit Hyperactivity Disorders by Decreasing Mind Wandering (OR29-04-19). Current Developments in Nutrition, 3(Suppl 1).
  5. Lyon MR, Kapoor MP, Juneja LR. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial. Altern Med Rev. 2011 Dec;16(4):348-54. PMID: 22214254.

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