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  • Gluten free

  • Dairy free

  • Soy free

  • Wheat free

  • Corn free

  • Milk free

  • Artificial preservative free

  • Yeast free

  • Artificial Color / Colour Free

  • Artificial Flavor / Flavour Free

Brain serotonin precursor; supports a sense of calmness and restful sleep‡

L-Tryptophan is an essential amino acid and a precursor for the synthesis of serotonin. Tryptophan crosses the blood-brain barrier and is converted to L-5-hydroxytryptophan (5-HTP), which in turn is converted into serotonin. Serotonin is an important neurotransmitter necessary for the regulation of appetite, mood, and melatonin production.‡
As a dietary supplement, adults take 2 capsules, 1-3 times daily, between meals or as directed by your health professional.


Serving Size: 2 Vegetarian Capsules

Amount Per Serving
Vitamin B6 ... 6.7mg
(as pyridoxal-5-phosphate)
L-Tryptophan ... 1,000mg
(as TryptoPure®)

Other Ingredients: Hydroxypropyl methylcellulose (capsule)

Gluten-free, non-gmo

TryptoPure® is a registered trademark of Ajinomoto AminoScience, LLC.
Warning: Not to be taken by pregnant or lactating women. If you have any health condition or are taking any medication, particularly psychiatric and antidepressant medication, consult your professional before use. 

Keep out of the reach of children.

Store in a cool, dry place. Use only if safety seal is intact.

L-Tryptophan

Douglas Labs

$54.99

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