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Doctor's Best

Suntheanine L-Theanine

Suntheanine L-Theanine

Item: DB118

  • Doctor's Best Suntheanine L-Theanine supplement

  • Promotes healthy stress management

  • Does not cause drowsiness, but may support healthy sleep

150 mg 90 Veg Caps

Retail $29.99
Save 49%
In Stock

Supplement Facts

Serving Size 1 Capsule

Servings Per Container 90 servings

  Amount Per Serving %Daily Value
Suntheanine® L-theanine 150 mg

†Daily Value not established.

Other ingredients: Microcrystalline cellulose, modified cellulose (vegetarian capsule).

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

Suitable for Vegans

Contains Nothing Other Than Listed Ingredients.

  • Gluten free
  • Vegan
  • Non-GMO

Suntheanine® is a registered trademark of NutriScience Innovations, LLC.

Shipping Weight

.12 lbs

  • Doctor's Best Suntheanine L-Theanine supplement

  • Promotes healthy stress management

  • Does not cause drowsiness, but may support healthy sleep

Doctor's Best Suntheanine® L-Theanine supplement supports relaxation without drowsiness to help manage stress and tension. Suntheanine is the premier, patented form of the amino acid L-theanine. Suntheanine is the purest form of L-theanine on the market today, derived from the amino acid in green tea that is responsible for the relaxation-inducing effect of tea consumption. Suntheanine has been shown to create an alert state of relaxation, and it may also support sleep quality and mental acuity.

Terms and Ingredient Definitions

Doctor's Best Suntheanine L-Theanine Reviews

Summary of Customer Ratings & Reviews

Customer Ratings & Reviews

Suntheanine L-Theanine is rated 4.8 out of 5 by 5.
Rated 5 out of 5 by from It works. L-theanine is to help one relax and isn't meant to be a sleep aid, yet it does help me sleep well.
Date published: 2016-01-30
Rated 5 out of 5 by from Great for Relaxation Suntheanine L-Theanine is an excellent supplement for those who are stressed. The supplement works within 15-30 minutes of taking and returns one to a more relaxed state of mind and body (just like a good cup of hot tea). This product was the most effective of the supplements I have taken in reducing stress and has helped me during emotionally fragile times to relax and regain control.
Date published: 2013-12-16
Rated 5 out of 5 by from I like Doctor's Best I like this brand of supplements, everything I have tried from them seems to be of high quality
Date published: 2013-10-17
Rated 5 out of 5 by from
Date published: 2013-08-16
Rated 4 out of 5 by from
Date published: 2013-04-16
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Why Shop Swanson® Brands?

"With my personal 100% money-back satisfaction guarantee, you have nothing to lose and great savings to gain."

Lee Swanson, Founder of Swanson Health Products

Risk-Free Purchase Guarantee on Doctor's Best Suntheanine L-Theanine

If you are dissatisfied for any reason, we'll give you a full refund and pay return shipping.

Swanson's Standards

We are dedicated to offering the highest quality products at the best price. Find out more about how we ensure such a high standard in everything we do.

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© 2017 Ratings based on results of the 2017 Survey of Supplement Users. More information at
© 2017 Swanson Health Products – Terms of Service