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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
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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


Posted by iHerb Customer on Nov 25, 2017 | Verified Purchase


Thanks for your feedback!

Does it's job

Posted by mikhailb on Nov 09, 2017 | Verified Purchase

Can't complain about this. Puts me asleep after 30-40 minutes of taking 3 pills. It's not like valerian or other herbs so it won't help with anxiety but will signal your body it's time to sleep. Kind of a much more powerful melatonin (which doesn't work for me at all).

Thanks for your feedback!

Messed my head up

Posted by iHerb Customer on Oct 28, 2017 | Verified Purchase

I decided to purchase this product for sleep it is recommended to take three and I took one and I was not able to think straight. I didn't know what day it was when I woke up. My friend was trying to organise something with me via text and in the end had to ring me as I was unable to comprehend the messages correctly. Then I sat outside and saw the shadow cast by my knee and thought it was something behind me.

Thanks for your feedback!

Seems to be helping

Posted by iHerb Customer on Oct 19, 2017 | Verified Purchase

After coming of medication, I had my first panic attack (in many years) after about 12 weeks, the L-Tryptophan give me the same headache as I got when I first went on the medication but hopefully without the other medication side effects. I hope it keeps working, I need to be very careful with my diet, anyone wanting to take tryptophan needs to do their own research about how it reaches the brain, do not rely on Doctors who are not up to date, science is constantly changing as more and better research is being undertaken.

Thanks for your feedback!

Not As Affective as the capsules

Posted by iHerb Customer on Aug 29, 2017 | Verified Purchase

I recommend the capsules over this pill form. I didn't realize I bought the wrong one. It works somewhat...but not near as affective. I'm going to stick it out with these, because I paid for them...can't wait to go back to the capsules!

Thanks for your feedback!