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Source Naturals, L-Tryptophan, 500 mg, 60 Capsules

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Source Naturals, L-Tryptophan, 500 mg, 60 Capsules

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Source Naturals, L-Tryptophan, 500 mg, 60 Capsules

In Stock
  • Expiration Date: 03/2021
  • Shipping Weight:
    0.18 lbs
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  • Product Code: SNS-01984
  • UPC Code: 021078019848
  • Package Quantity: 60 Capsules
  • Dimensions:
    2.4 x 2.4 x 4 in, 0.15 lbs
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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 positive mood. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response and sleep/wake cycles. 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 capsule three times daily, between meals and preferably with fruit juice. To support restful sleep, take 3 capsules before bed.

Other Ingredients

Gelatin (capsule), silica, magnesium stearate, dibasic calcium phosphate, and microcrystalline cellulose.

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


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

Store in a cool, dry place.

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.

Supplement Facts
Serving Size: 3 Capsules
Servings Per Container: 20
  Amount Per Serving: % DV
Iron (naturally occurring) 575 mcg 3%
L-Tryptophan 1.5 g
†Daily Value not established.
iHerb Customer Reviews

It used to work for insomnia

Posted by iHerb Customer on Jan 10, 2018 | Verified Purchase

Because it worked before, so I bought 3 bottles this time. Unfortunately, it was not effective any more.

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Great help with sleep

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

This product was recommended by a medical practitioner to assist with sleep problems, I have found it to be a big help with this.

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Posted by iHerb Customer on Dec 14, 2017 | Verified Purchase

I combine 1500mg l-tryptophan, 1500mg Graviola, 300 mg 5-HTP, 400mg magnesium citrate and 1 gram phenibut for sleep and it works well for about 2-3 nights then the body attenuates, looking for other combos to add to my rotation to handle 7 nights of good rest.

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Sleepless nights

Posted by iHerb Customer on Nov 09, 2017 | Verified Purchase

This was my go to when I could not sleep Until I found out about magnesium and taking it before bed time . sleep like a baby now . L tryptophan is good alternative though.

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Works to put me to sleep

Posted by Sandra on Nov 03, 2017 | Verified Purchase

When I need to fall into a deeper sleep I use this.

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