Source Naturals L-Tryptophan

120 capsules | $0.22/Capsule


(11% Off)
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Why You’ll Love It

The essential amino acid L-tryptophan is the precursor for the synthesis of melatonin and serotonin, a hormone and a neurotransmitter involved with mood and stress response. It helps support relaxation, restful sleep, and a positive outlook. This tryptophan tablet includes vitamin B-6, which is required to convert tryptophan to serotonin. If needed, L-tryptophan is converted to niacin in the body, an important B vitamin. Source Naturals L-Tryptophan is extremely pure and is regularly tested to ensure the highest standards of quality.

SKU: 021078019855

About This Brand

Source Naturals

“Take responsibility for your health.” That’s the mantra Source Naturals has championed since the early 1980s, and the company’s line of more than 600 supplements and wellness products help people do just that. Even today, federal government regulations around supplement products are still lax, and don’t require detailed labeling. So it’s important to double-check what’s really going inside each...
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Other Ingredients: microcrystalline cellulose, stearic acid, modified cellulose gum, and silica

Disclaimer: Information, statements, and reviews regarding products have not been evaluated by the Food and Drug Administration. Results vary person to person, and there is no guarantee of specific results. Thrive Market assumes no liability for inaccuracies or misstatements about products.

Nutrition information

Serving Size:
1 tablet
Servings Per
Amount per serving
% daily value
Vitamin B-6 (as pyridoxine HCl)
20 mg
Iron (naturally occurring)
390 mcg
1 g
† Daily Value Not Established

Warning: 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. This product may cause drowsiness. 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. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

13 Members have left reviews!


Posted   by Hawk from OJAI, California
Verified Purchase
helpful for sleep. i take 1 capsule, not the high dose recommended on the label. not sure about the gelatin capsule though.
Helpful review?

Seems to work really well

Posted   by Lorraine from Clifton Park, New York
Verified Purchase
My husband takes this along with other sleep aids - but this is the one that really seemed to make it all work together.
Helpful review?

Quality Brand

Posted   by Sarah from South Lake Tahoe, California
Verified Purchase
Good price for a quality product
Helpful review?


Posted   by Monica from GLEN GARDNER, New Jersey
Verified Purchase
Helpful review?

Sleep help

Posted   by Kyle from HILLSBOROUGH, New Jersey
Verified Purchase
Helps on nights when I can't seem to fall asleep. Sometimes I use this tryptophan and sometimes I use the Source Naturals GABA Calm. I like them both.
Helpful review?

This truly helps me sleep

Posted   by Jennifer from BROOKLYN, New York
Verified Purchase
I absolutely love this! I live in NYC, so sleeping through the night is sometimes a challenge. This gives me a deep sleep and helps me fall asleep faster.
Helpful review?

good price

Posted   by CHRISTINA from Santa Cruz, California
Verified Purchase
My doctor recommended taking this before bed for improved sleep. I was buying it at a pharmacy and it cost $10 more a bottle. I was glad to find this on thrive.
Helpful review?

Helps with sleep

Posted   by Wendy from FLEETWOOD, Pennsylvania
Verified Purchase
Quality supplement that helps me sleep.
Helpful review?

Purchased for a relative with insomnia

Posted   by Roxanne from SAN JOSE, California
Verified Purchase
She's tried everything. I'm hoping this assortment of ingredients will help her. I will update this review after she's used it for a bit.
Helpful review?

Sleep Necessity

Posted   by Denise from MOUNT HOLLY, New Jersey
Verified Purchase
Great product...great price!
Helpful review?
(Displaying 10 of 13 reviews)

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