Can L-Theanine Be Used to Treat ADHD?

Some research supports the beneficial effects of this amino acid.

Glass of green tea which is a source of L-theanine

Getty / LamiadLamai

ADHD is a condition that is characterized by problems with focus, hyperactivity, and impulsiveness. While there is no cure for ADHD, there are treatments that can help manage the symptoms.

L-theanine is an amino acid that is found naturally in green tea. L-theanine has been shown to have a calming effect and can help reduce anxiety and stress. Some research has also suggested that L-theanine may be helpful in treating ADHD. However, more research is needed to confirm these effects.

What Is ADHD?

ADHD is a mental disorder that is characterized by problems with attention, hyperactivity, and impulsiveness. Symptoms of ADHD can include difficulty staying focused on tasks, trouble paying attention, acting without thinking, and being easily distracted. ADHD affects children and adults of all ages and can lead to problems at home, school, work, or in relationships.

ADHD Symptoms

Symptoms of ADHD generally fall under two umbrella types: inattentiveness and hyperactivity/impulsivity. According to the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), a person must display at least six symptoms from one or both categories to be diagnosed with ADHD.

Inattention symptoms may include:

  • Failing to give close attention to details or making careless mistakes in schoolwork, at work, or with other activities.
  • Having trouble sustaining attention in tasks or play activities.
  • Not seeming to listen when spoken to directly.
  • Not following through on instructions and failing to finish schoolwork, chores, or duties in the workplace.
  • Having trouble organizing tasks and activities.
  • Avoiding, disliking, or being reluctant to engage in tasks that require sustained mental effort.
  • Losing things necessary for tasks or activities.
  • Becoming easily distracted by extraneous stimuli.
  • Being often forgetful in daily activities.

Hyperactivity/Impulsivity symptoms may include:

  • Fidgeting with hands or feet or squirming when seated.
  • Leaving their seat in situations when remaining seated is expected.
  • Running or climbing excessively in situations where it is inappropriate.
  • Having difficulty playing or engaging in leisure activities quietly.
  • Being “on the go” or acting as if “driven by a motor”.
  • Talking excessively.
  • Blurting out answers to questions before they have been completed.
  • Having difficulty waiting for one’s turn.
  • Interrupting or intruding on others by finishing their sentences, talking at the same time, or butting into conversations.

How Is ADHD Treated?

There is no cure for ADHD, but there are treatments that can help manage the symptoms. Treatment typically involves a combination of medication and therapy.

Medication

Stimulant medications are the most commonly used type of medication to treat ADHD. These drugs work by increasing levels of dopamine and norepinephrine in the brain, which can help improve focus and attention. Common stimulant medications used to treat ADHD include methylphenidate (Ritalin, Concerta) and amphetamines (Adderall, Vyvanse).

Psychotherapy

Behavioral therapies, such as cognitive-behavioral therapy (CBT), can also be helpful in treating ADHD. CBT can help people with ADHD learn to better manage their symptoms. Other therapies, such as parent training and education, social skills training, and occupational therapy, can also be helpful in treating ADHD.

What Is L-Theanine?

L-theanine belongs to a class of compounds known as amino acids. Amino acids are the building blocks of proteins. L-theanine is found naturally in green tea. It is also available in supplement form.

L-theanine has been shown to have a calming effect and can help reduce anxiety and stress. Some research also suggests that L-theanine may help improve attention and focus.

Benefits of Taking L-Theanine for ADHD

L-theanine may offer a natural way to treat ADHD. L-theanine can help improve attention and focus and has a calming effect on the mind. It is also relatively safe, with few side effects. If you are considering taking L-theanine for ADHD, it is important to talk to your doctor first.

How Can I Get L-Theanine?

You can get L-theanine from green tea or in supplement form. L-theanine supplements are also available and are generally considered safe. However, as with any supplement, it is always best to talk to your doctor to ensure that it's safe for you.

Who Can/Can’t Take L-Theanine?

L-theanine is generally considered safe for most people. However, there are some people who should not take L-theanine. These include pregnant or breastfeeding women, children, and people with pre-existing medical conditions. If you have any concerns about taking L-theanine, talk to your doctor.

How Much L-Theanine Should You Take?

The amount of L-theanine you should take depends on a variety of factors, including your age, weight, and health condition. It is always best to talk to your doctor before taking L-theanine or any other supplement.

Side Effects of L-Theanine

L-theanine is generally well tolerated and has few side effects. The most common side effect is nausea. If you experience any side effects, stop taking L-theanine and talk to your doctor.

L-theanine may interact with certain medications, such as antidepressants and blood pressure medications. If you are taking any medications, it is always best to talk to your doctor before taking L-theanine or any other supplement.

Is L-theanine an Effective Treatment for ADHD?

A small study published in the journal Scientific Reports found that L-theanine improved attention in boys with ADHD. The study looked at 5 boys with ADHD between the ages of 8 and 15. The boys were given either 2.5 mg/kg of L-theanine, 2.0 mg/kg of caffeine, their combination, or a placebo prior to engaging in a task. Boys who had taken L-theanine with caffeine showed significantly improved attention and focus compared to those who had taken the placebo.

Regarding whether L-theanine might help with sleep disturbance in ADHD, a systematic review study published in the Journal of Child and Adolescent Psychopharmacology found that L-theanine may help improve sleep efficiency in those with ADHD.

While there is some promising research on the use of L-theanine for ADHD, more research is needed to confirm these findings.

Does L-Theanine Need to Be Combined With Caffeine? 

L-theanine can be taken alone or in combination with caffeine. A study published in the journal Nutritional Neuroscience found that L-theanine and caffeine improved attention and focus in adults.

Twenty male participants were given either 200 mg of L-theanine, 160 mg of caffeine, their combination, one cup of black tea, or a placebo. Participants who had taken L-theanine, caffeine, or their combination showed significantly improved attention and focus compared to those who had taken the placebo.

A Word From Verywell Mind

If you are considering taking L-theanine for ADHD, it is important to talk to your doctor first. While there is some promising research on the use of L-theanine for ADHD, more research is needed to confirm these findings. L-theanine may interact with certain medications, so it is always best to talk to your doctor before taking L-theanine or any other supplement.

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11 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.
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