L-Theanine
An amino acid found naturally in tea leaves that promotes relaxation without drowsiness. Excellent for focus, anxiety reduction, and sleep quality — particularly effective when combined with caffeine.
Pharmacists & Nutrition Researchers · Updated March 2026
100–400 mg
Dosage
morning
Timing
Moderate
Evidence
2 cited
Studies
Benefits of L-Theanine
Promotes calm focus without sedation
Reduces anxiety and stress perception
Improves sleep quality when taken before bed
Enhances cognitive performance when paired with caffeine
May reduce blood pressure in stressful situations
How L-Theanine Works
L-theanine crosses the blood-brain barrier and increases alpha brain wave activity (associated with relaxed alertness). It modulates GABA, serotonin, and dopamine levels, and reduces glutamate excitotoxicity. It also increases BDNF (brain-derived neurotrophic factor).
Recommended Dosage
Well-absorbed on empty stomach. For focus: take 100-200mg with caffeine (tea or coffee). For sleep: take 200-400mg 30-60 minutes before bed. Suntheanine is a patented, well-researched form.
Who Should Avoid L-Theanine
Key Research
L-theanine and caffeine combination effects (2008)
The combination improved speed and accuracy of attention tasks more than either alone
DOI: 10.1007/s00213-008-1300-yL-theanine for sleep and anxiety (2019)
200mg/day reduced stress and improved sleep quality scores in adults
DOI: 10.3390/nu11102362Recommended L-Theanine Brands in India
Carbamide Forte L-Theanine 200mg with Vitamin B Complex
Carbamide Forte
"Clinical dose (200mg) of L-theanine paired with B-complex for enhanced cognitive and stress-relief benefits."
Carbamide Forte L-Theanine 200mg with Vitamin B Complex
Carbamide Forte
"Clinical dose (200mg) of L-theanine paired with B-complex for enhanced cognitive and stress-relief benefits."
Products are selected based on quality, testing, and purity — not affiliate economics. See our selection criteria.
Works Well With
Frequently Asked Questions
What is L-Theanine used for?
An amino acid found naturally in tea leaves that promotes relaxation without drowsiness. Excellent for focus, anxiety reduction, and sleep quality — particularly effective when combined with caffeine.
What is the recommended dosage of L-Theanine?
The clinically studied dosage range is 100–400 mg per day. Well-absorbed on empty stomach. For focus: take 100-200mg with caffeine (tea or coffee). For sleep: take 200-400mg 30-60 minutes before bed. Suntheanine is a patented, well-researched form.
When is the best time to take L-Theanine?
L-Theanine is best taken in the morning. Well-absorbed on empty stomach. For focus: take 100-200mg with caffeine (tea or coffee). For sleep: take 200-400mg 30-60 minutes before bed. Suntheanine is a patented, well-researched form.
Is L-Theanine safe?
L-Theanine is generally considered safe at recommended dosages. However, it may be contraindicated for: Generally very safe with no major contraindications, Use caution if on blood pressure medications. Always consult a healthcare professional before starting any supplement.
Is L-Theanine vegetarian?
L-Theanine supplements are available in vegetarian form. Check the specific product label for capsule ingredients.
Can I take L-Theanine with other supplements?
Be aware of these interactions: May enhance effects of blood pressure medications. Synergistic with caffeine for focus. May enhance effects of sedative medications
Is L-Theanine right for you?
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