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Doctor's Best, Best L-Tryptophan, Tryptopure, Powder, 50 g (Discontinued Item)

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Out of Stock - Discontinued
  • Shipping Weight: 0.26 lbs (0.12 kg)
  • Product Code: DRB-00145
  • UPC Code: 753950001459
  • Package Quantity: 50 g
  • Dimensions: 2.9 x 2.9 x 3.1 in, 0.2 lbs (0.09 kg)
  • Doctor's Best uses exclusively the Tryptopure brand of tryptophan, manufactured by Ajinomoto of Japan.
Product Overview


  • Science-Based Nutrition
  • Dietary Supplement
  • USP Pharmaceutical Grade
  • Featuring Ajinomoto's TryptoPure
  • Suitable for Vegetarians

L-tryptophan is an essential amino acid (protein building block) in human nutrition. Essential amino acids are not synthesized by the body and must be obtained in the diet. The L-tryptophan in this product is manufactured and tested for purity according to the Japanese Pharmacopeia (JP) and the United States Pharmacopeia (USP) standards.

Suggested Use

1 scoop daily, or as directed by a health practitioner. For optimum absorption, take separately from protein-containing foods and dietary supplements containing protein or amino acids. Take with water or juice.

Other Ingredients


Contains nothing other than listed ingredients.

Supplement Facts
Serving Size: 1 scoop (500 mg)
Servings Per Container: 100 servings
  Amount Per Serving % Daily Value
Ajinomoto L-Tryptophan 500 mg
† Daily Value not established.
iHerb Customer Reviews

Good product but hard to swallow

Posted by NBPT100 on Jul 23, 2013

I gave this three stars only because it does not mix well in water and tastes awefull. But it does help with better sleep. It is cheaper than capsules but I think I will spring for the capsules next time. If you have a capsule filling machine you could try that approach and not have to deal with mixing and trying to get it down your throat. It can be time consuming. L-tryptophan is a precursor to 5-HTP. Some people find that 5-HTP does not work so well for them. If this is you, L-tryptophan is a good alternative. Try it with a small amount of B6 and B3 as they are cofactors and it may work better. If you found this review helpful, kindly visit my home page and see more value added reviews. Peace and good health.

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Great for a calm mind and sleep

Posted by coconut on Jul 01, 2012

I used this to calm my mind from stress and to sleep better. I also have had relief from stressors such as work. I can take it at work and not have to worry about prescriptions. It won't make you drowsy. Just less stress and better to cope.  Take on an empty stomach for best results! I like that this product is pure and contains no other ingredients. I buy capsuled L-Tryptophan for my dog. He is easily upset and scared of thunderstorms. I don't like medicating him so after some research I tried this. He is more calm and I feel better that this is more natural than the meds his vet gave him.  

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Posted by Scottishdave on Jun 15, 2012

Did not provide myself with the benefits claimed.

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Life long insomnia is over!

Posted by Reviewer3105168 on Jan 06, 2012

I've suffered from horrible insomnia my entire life and absolutely nothing has worked so consistently and for an entire 8 hours of sleep even under extreme stress. I do take between 2 and 3 scoops however and I seem to have no problem taking on an empty stomach. Thank you Dr's. Best and iherb!

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Posted by Reviewer1821400 on Dec 15, 2011

Very good aid for sleep! And also good feeling during day.

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