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Doctor's Best L-Theanine with Suntheanine 150 mg 90 Veggie Capsules

Helps promote a relaxed state without drowsiness

Helps ease stress and occasional nervous tension

Helps promote a healthy mood and alertness

Helps diminish normal symptoms of Pre-Menstrual Syndrome (PMS)

  • Buy 2 for £28.25 each and save 5%
  • Buy 3 for £26.77 each and save 10%
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Free UK deliveryFREE UK delivery over £30
European delivery from £4.95
Refund or exchange60 day refund
Or exchange available
Suntheanine is the premier, patented form of the amino acid L-theanine. Suntheanine is the purest form of L-theanine on the market today.

Nutritional Information

Ingredients  Typical Amount per Serving %RI*
L-theanine (Suntheanine) 150 mg **

* Reference Intake
** Reference Intake value not established



Microcrystalline cellulose, hypromellose (vegetarian capsule), silicon dioxide.

Free From

Gluten Free, Soy Free

Directions of Use

Take 1 capsule daily away from food, or as recommended by a nutritionally-informed physician.


Food supplements should not be used as a substitute for a varied diet. Do not exceed the stated dosage. Store in a cool, dry place, protected from light and heat. Keep out of sight and reach of children.


Not recommended for individuals who are pregnant and nursing.
Product Questions
About The Brand
About The Brand

Doctor's Best

Bigvits are proud to introduce you to Doctor's Best, a brand dedicated to creating a healthier world filled with thriving families, positivity, and happiness. Founded by a physician in 1990, they set out with a vision to develop research-backed nutritional supplements. Today, with over 30 years of experience, Doctor's Best remains committed to their science-based approach to nutrition. They source top-quality ingredients and collaborate with industry-leading manufacturers to produce supplements that enhance people's well-being. At Bigvits, we gladly offer Doctor's Best's science-driven solutions for a healthier lifestyle.

Delivery & Returns

Delivery & returns

  • Free Delivery

    Same day dispatch on all orders placed before 14:30 (GMT) and free UK delivery on orders over £30

  • Click and Collect

    Click and Collect is available for customers who live within 25 miles of our Driffield warehouse

  • International Delivery

    European delivery options vary by country. Prices start from £4.95. Enter your address at checkout for a price

  • No Quibble Returns

    99% of customers love our products. We are confident you will too. 60 day money back guarantee