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Source Naturals



Item:  SN389

  • 500 mg L-tryptophan capsules

  • Promotes positive mood

  • Supports relaxation and restful sleep

500 mg 120 Caps

MSRP $43.50
Save 30%
Yes! I want free shipping over $50 on my next automatic shipment of this item.  days. Learn more
In Stock

Supplement Facts

Serving Size 3 Capsules

Servings Per Container 40

  Amount Per Serving % Daily Value
Iron (naturally occurring) 575 mcg 3%
L-Tryptophan 1.5 g

†Daily Value not established.

Other ingredients: gelatin (capsule), dibasic calcium phosphate, microcrystalline cellulose, silica, and magnesium stearate.

Suggested Use: 1 capsule three times daily, between meals and preferably with fruit juice. To support restful sleep, take 3 capsules before bed.

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


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.

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

Shipping Weight

.27 lbs

  • 500 mg L-tryptophan capsules

  • Promotes positive mood

  • Supports relaxation and restful sleep
Source Naturals L-Tryptophan promotes positive mood, relaxation and sleep. This essential amino acid plays a part in the synthesis of melatonin and serotonin, the hormones involved with mood, stress response and sleep/wake cycles. L-Tryptophan also supports the body's immune system. Hypoallergenic: contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, salt, starch, preservatives or artificial color, flavor or fragrance.

Source Naturals L-Tryptophan Reviews

Summary of Customer Ratings & Reviews

Customer Ratings & Reviews

L-Tryptophan is rated 5.0 out of 5 by 15.
Rated 5 out of 5 by from Sleep well! Sleep is so essential and this product helps bring a calming down in the brain when taken before bedtime.
Date published: 2015-11-18
Rated 5 out of 5 by from Super product I was taking Melatonin alone, which was working fairly well, but when I added L-Tryptophan, I have been sleeping like a baby at night! Won't go to bed without it any more.
Date published: 2014-04-10
Rated 5 out of 5 by from my favorite Always reliable and consistent quality
Date published: 2013-12-14
Rated 5 out of 5 by from Great Sleep Aide My husband uses it regularly to help him sleep. He's tried other sleeping aides , but this is the only one that has worked for him.
Date published: 2013-12-10
Rated 5 out of 5 by from It helps me fall asleep and have a restful sleep.
Date published: 2013-08-08
Rated 5 out of 5 by from Helpful with relaxation I give L-Tryptophan to my elderly mother and to my teen son, both of whom have sleep issues. It seems to help them relax and fall asleep more quickly at night.
Date published: 2013-06-19
Rated 5 out of 5 by from Excellent product, excellent price This product is outstanding and the price at Swanson's Vitamins is excellent.
Date published: 2013-03-27
Rated 5 out of 5 by from The Best I've Found I am so thrilled to have found this product. It gives me a restful night's sleep, and it is very economical. I simply love it!!!
Date published: 2013-03-14
Rated 5 out of 5 by from Outstanding product This product is outstanding in every way. It definitely has a claming effect.
Date published: 2013-03-04
Rated 5 out of 5 by from EXCELLENT I've used different brands and I finally found one I trust and it works the way it should!!
Date published: 2013-02-15
Rated 5 out of 5 by from Good quality! I've been using this brand of L-tryptophan for a couple of years, and have been completely satisfied.
Date published: 2012-10-22
Rated 5 out of 5 by from This is such a great product, a great blend that really works & the value on Swanson site is fabulous----I pray they continue this offering in this quantity--Is stopping my trips to a competitive "V Shoppe" for the value & convenience of offering this quantity...
Date published: 2012-08-08
Rated 5 out of 5 by from Great, effective product My mom and I both love this product. Helps you get a restful sleep. One awesome add on benefit is if you forget to take it or think you don't need it and then 4am rolls around and you can't sleep, it's fine to take it, you'll at least get a few solid hours and it won't make you drowsy in the morning.
Date published: 2012-03-22
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