2-Amino-4- (ethylcarbamoyl) Butyric Acid, 5-N-ethylglutamine, Gamma-glutamylethylamide, L-Theanine, L-Théanine, N-Éthyl-L-Glutamine, Teanina, Théanine.<br/><br/>


Overview Information

Theanine is an amino acid (a building block for proteins) found in green tea.

People use theanine for treating anxiety and high blood pressure, for preventing Alzheimer’s disease, and for making cancer drugs more effective.

How does it work?

Theanine has a chemical structure very similar to glutamate, a naturally occurring amino acid in the body that helps transmit nerve impulses in the brain. Some of the effects of theanine appear to be similar to glutamate, and some effects seem to block glutamate.


Uses & Effectiveness?

Insufficient Evidence for

More evidence is needed to rate the effectiveness of theanine for these uses.

Side Effects

Side Effects & Safety

Theanine is POSSIBLY SAFE when used by mouth, short-term. Theanine has been used one time per week for 3 weeks. It is not known if use for longer periods of time is safe.

Special Precautions & Warnings:

Pregnancy and breast-feeding: There is not enough reliable information about the safety of using theanine if you are pregnant or breast-feeding. Stay on the safe side and avoid use.



Moderate Interaction

Be cautious with this combination

  • Medications for high blood pressure (Antihypertensive drugs) interacts with THEANINE

    Theanine seems to decrease blood pressure. Taking theanine along with medications for high blood pressure might cause your blood pressure to go too low.<br/><br/> Some medications for high blood pressure include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDiuril), furosemide (Lasix), and many others.

  • Stimulant drugs interacts with THEANINE

    Stimulant drugs speed up the nervous system. By speeding up the nervous system stimulant medications can make you feel jittery and speed up your heartbeat. Theanine might work to slow down the nervous system. Taking theanine along with stimulant medications might decrease the effectiveness of stimulant medications.<br/><br/> Some stimulant drugs include diethylpropion (Tenuate), epinephrine, phentermine (Ionamin), pseudoephedrine (Sudafed), and many others.




  • Mental performance: A single dose of 100 mg of theanine before a test has been used. Theanine has also been used in combination with caffeine. Combination doses have ranged from 30-100 mg of caffeine and 12-100 mg of theanine.

View References


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More Resources for THEANINE

CONDITIONS OF USE AND IMPORTANT INFORMATION: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

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