2-Amino-4- (ethylcarbamoyl) Butyric Acid, 5-N-ethylglutamine, Gamma-glutamylethylamide, L-Theanine, L-Théanine, N-Éthyl-L-Glutamine, Teanina, Théanine.<br/><br/>
Overview InformationTheanine 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
- Anxiety. Early research suggests that taking theanine might make unstressed people feel more tranquil. However, theanine does not seem to have this effect when used by people who are anxious.
- Preventing dementia including Alzheimer's disease.
- Treating high blood pressure.
- Increasing the treatment effects of cancer drugs.
- Other conditions.
Side Effects & SafetyTheanine 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.
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.
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