L-Theanine Overdose – Care Needed

Although L-Theanine may be a good nootropic option for you please avoid L-Theanine Overdose.

L-Theanine is useful to help with mental problems like lack of focus and clarity.

Focus lens

It is a powerful sleep inducer that has already improved sleep patterns and quality among many users.

Mechanism of Action

L-Theanine works in the brain. In particular, it works on certain types of neurotransmitters and receptors.


These include:

  • Glutamate – L-Theanine is a glutamate-like binding agent, and therefore it attaches itself to glutamate receptors. The action facilitates the sending and receiving of signals between nerve cells.
  • Serotonin – L-Theanine increases serotonin production. Serotonin in the brain is known to be the regulator of mood, happiness and anxiety.
  • Dopamine – The main neurotransmitter acting in the reward circuit, it increases when a person feels pleasure and decreases when the pleasure ebbs. The lowering down of this neurotransmitter signals the body to ask for the repetition of the pleasurable experience.
  • Gamma Amino Butyric Acid – (or GABA for short) – GABA is responsible for stopping nerve communication in times that a person feels nervous. L-Theanine can increase the levels of this neurotransmitter in the brain.
  • Glycine – This is an amino acid that functions as a GABA agonist. L-Theanine supports glycine. Glycine has both inhibitory and excitatory effects in the brain.

With an ability to cross the blood-brain barrier, L-Theanine is thought to also have the capacity to produce psychoactive effects. Preliminary findings suggest that L-theanine, when combined with caffeine, has the potentials of improving cognition, physical stress, mental stress and mood. More clinical studies are required to provide stronger evidence to these claims.

Theanine has been shown to promote production of alpha wave in the brain. There are changes in the alpha waves as well as among those who consume green tea with small amounts of L-Theanine.

If indeed L-Theanine deserves the credit for these effects from green tea, then it is this substance in the drink that produces relaxation of the body and the mind, calming of thoughts and reduction of nervousness among drinkers. Additional benefits of increasing alpha waves in the brain include increased creativity levels, improved logical and problem solving abilities, emotional stability, increased levels of serotonin, and enhanced immune functions.


L-Theanine is a very promising substance in terms of its ability to improve the quality of life of people with mental health challenges. Although further studies on it are demanded by people with well-meaning intentions, current testimonial evidence on its efficacy is pretty strong.

For people with doubts, it will be ideal for them to check reviews of L-Theanine supplements online. We’re using some of the users’ feedbacks in this section.

  • Ability to improve sleep – Some supplement users think that the products they are using are the ones to be credited for their improved quality of sleep. They can stay asleep longer and fall asleep easier.
  • Increased positivity in facing future challenging situations – Some people reported that they felt less anxious after using these products. It makes them look forward to stressful situations like delivering a speech or taking very important examinations.
  • Ability to reduce the negative effects of coffee consumption – Some heavy drinkers of coffee reported that they no longer worry about the negative side effects of drinking coffee. Those negative effects are being negated by L-Theanine, they added.
  • Helpful in multitasking – L-Theanine is credited for experiences where the person has to battle with stress over multiple tasks that need to be done at the same time. Some people even reported that they only take a pill or two per month to cope with highly stressful days.
  • Liver protection – L-Theanine has been found to prevent alcoholic liver injury.
  • Memory and learning enhancement – L-Theanine promotes better memory and faster learning.
  • Cancer – Some reports say that L-Theanine increases potency of cancer medications.
  • Helps fight infection – L-Theanine supports immune system functions.

Side Effects

Different individuals have different bodily reactions to L-Theanine. It is important to talk with your doctor on the right dosage that should be given to you. Factors affecting how severe side effects can be experienced are dosage, frequency of use, interactions with other substances, and concentration of L-Theanine in the supplement one is using. L-Theanine overdose occurs when more than 1200 mg is taken by the body on a daily basis.

Common side effects due to overdose include:

  • Nausea
  • Dizziness
  • Headache

As of the moment, there are no severe adverse side effects that have been reported. There are complaints from some quarters that the promised effects don’t occur in some users, but these are very few cases and may be attributable to differences in users’ bodily chemistry and reactions to the substance.