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Source Naturals, L-Tryptophan, 500 mg, 120 Tablets

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Source Naturals, L-Tryptophan, 500 mg, 120 Tablets

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Source Naturals, L-Tryptophan, 500 mg, 120 Tablets

In Stock
120 Tablets
120 Tablets
60 Tablets
  • Expiration Date: 05/2021
  • Shipping Weight:
    0.3 lbs
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  • Product Code: SNS-01980
  • UPC Code: 021078019800
  • Package Quantity: 120 Tablets
  • Dimensions:
    2.2 x 2.2 x 4 in, 0.25 lbs
    Switch to Metric units
Frequently Purchased Together
Product Overview


  • Dietary Supplement
  • Mood, Relaxation, Sleep
  • Non-GMO Validated

The essential amino acid L-tryptophan helps support relaxation, restful sleep, and feeling better. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response. L-Tryptophan also supports immune functions because it is the body's precursor to the kynurenines that regulate immunity. If needed, L-tryptophan converts to niacin in the body, which supports circulation, a healthy nervous system, the metabolism of food, and the production of hydrochloric acid for the digestive system. Source Naturals L-Tryptophan is extremely pure and is regularly tested to ensure the highest standards of quality.

Suggested Use

1 tablet three times daily, between meals and preferably with fruit juice. To support restful sleep, take 3 tablets before bed.

Other Ingredients

Dibasic calcium phosphate, stearic acid, modified cellulose gum, and silica .

Suitable for vegetarians and Hypoallergenic: Contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.


Caution: If you are pregnant, may become pregnant, breastfeeding, or are taking medications such as SSRIs or MAOIs consult your health care professional before using this product.

Store in a cool, dry place.

Do not use if either tamper-evident seal is broken or missing. Keep out of the reach of children.

Supplement Facts
Serving Size: 3 Tablets
Servings Per Container: 40
  Amount Per Serving %DV
Calcium 52 mg 5%
Iron (naturally occurring) 570 mcg 3%
L-Tryptophan 1.5 g
†Daily Value not established.
iHerb Customer Reviews

Great Product

Posted by iHerb Customer on Jan 27, 2018 | Verified Purchase

Great product, has helped with my sleep problems.

Thanks for your feedback!

Feeling better

Posted by iHerb Customer on Jan 24, 2018 | Verified Purchase

This product gives me a sounder sleep, and does a good job of reducing irritability from low mood .

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Love it

Posted by iHerb Customer on Jan 06, 2018 | Verified Purchase

l-tryptophan is wonderful for anxiety

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be cautious!

Posted by somethingclever on Dec 24, 2017 | Verified Purchase

i took one of these and nearly had a panic attack, my heart was pounding for over an hour. too afraid to take again. be careful if considering

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Posted by iHerb Customer on Dec 16, 2017 | Verified Purchase

When I first started taking this supplement for tremors, it made me feel incoherent when I would take it during the day. I have started taking it just before bed, and it seems to be helping improve my symptoms. One side affect I get is sleep paralysis occasionally while taking the product. On the plus side, I have not noticed any withdrawal affects if I stop or forget to take it. It has some "other" ingredients that are a bit questionable like silica, but I have not noticed any adverse reactions to these other ingredients. I still wish there was a pure or herbal form of this supplement. Overall, I am happy with the product.

Thanks for your feedback!