When to take it
In stressful situations, in the morning with coffee or in the evening before bed.
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Sleep & calmWeak evidence
L-theanine
Also known as: theanine
L-theanine is an amino acid from green tea that supports relaxed alertness without sedation. It is often combined with caffeine.
What it is used for
- Focus when combined with caffeine – moderate evidence
- Reducing stress and tension – weak evidence
- Sleep quality – weak evidence
Forms and how they differ
L-theanine
pure form, usually 100–200 mg per capsule
patented forms
pure L-isomer; effect similar to standard L-theanine
Pairs well with
Works well with caffeine, magnesium and glycine.
Do not combine / separate
Use caution with sedatives and blood pressure medicines – it may add to their effect.
Watch out for
Not recommended in pregnancy or breastfeeding due to lack of data. If you have low blood pressure, liver or kidney disease or take medicines, consult your doctor.
Safety
Generally well tolerated at usual doses. Do not exceed the label dose.
Practical tip
If coffee makes you jittery, try it with 100–200 mg of L-theanine – the effect is smoother.
Products containing L-theanine 13
GABA + L-theanineliposomal
GABA + Taurine + L-theanine 500 mgchewable · 500 mg / tablet
L-theanine + Lemon balmextract
L-theanine + Inositolfree form
L-theanine 100 mgfree form · 100 mg / capsule
L-theanine 200 mgfree form (Suntheanine) · 200 mg / capsule
L-theanine + Inositol 200 mgfree form · 200 mg / capsule
L-theaninefree form
L-theanine green tea extract 40 % 100 mggreen tea extract 40 % · 100 mg / capsule
L-theanine 100 mg100 mg / capsule
L-theanine 200 mg200 mg / capsule
Caffeine + L-theaninenatural caffeine
Magnesium + Glycine + L-theaninepowder
How to read the evidence rating
Strong evidenceModerate evidenceWeak evidenceNo evidence
Strong = several good human studies or official recommendations; moderate = promising but smaller studies; weak = few studies or mixed results; no evidence = claims not confirmed.
Combination check
Select the supplements you take and, if relevant, your medicines. We show what interferes, what needs a time gap and what to watch out for.
Check L-theanine with othersWhich supplements do you actually need?
Fénix Methode picks them from your blood results and schedules when to take what – no needless purchases.
From the same group
5-HTPWeak evidenceApigeninWeak evidenceCBDWeak evidenceChamomileWeak evidenceGABAWeak evidenceLavenderModerate evidence
Important notice
This information is educational and does not replace advice from a doctor or pharmacist. We do not give medicine dosages. Supplements are no substitute for a varied diet; if pregnant, breastfeeding, ill or on medication, consult a doctor first.