L-Tryptophan Powder
by NOW · powder · 2 oz.
- On the market (NIH)
- UPC 7 33739 00263 1
- DSLD label 53458
- Serving 2 tsp (1 g)
- 57 servings
L-Tryptophan Powder by NOW lists one ingredient: 950 mg of L-tryptophan per serving of 2 tsp. Its current label entered the NIH Dietary Supplement Label Database on November 24, 2015.
What is in L-Tryptophan Powder?
Each row as the label prints it, per serving of 2 tsp. The capsule beside an amount places it among every product in the NIH database that lists the same ingredient: the bar is the middle half of their amounts, the line in it the median, the whiskers the 10th and 90th percentiles; the green tick is the FDA Daily Value and the red dashed tick the adult upper limit (IOM).
| Ingredient | Amount | % DV | Among products listing it |
|---|---|---|---|
| L-TryptophanL-Tryptophan Note: free-form | 950 mg | Higher than 91% of 605 products listing tryptophan (median 123 mg). Per day at the most servings: 2,850 mg. |
Source: NIH ODS Dietary Supplement Label Database, label 53458 (entered November 24, 2015), version 9.4.0. See the label on DSLD. Amounts are what the maker printed; DSLD does not test products. Daily Values: the FDA's Daily Value page.
Is that a lot?
The rows in the top or bottom tenth of the products that list the same ingredient, and any above the adult upper limit at the most servings a day the directions give:
- Its 950 mg of L-tryptophan (filed by NIH under tryptophan) is higher than 91% of the 605 tryptophan products that print an amount; 54 list more.
The NIH database records 2 to 3 servings a day from the label's directions; its % Daily Values are for adults and children 4 or more years of age. The directions as printed are further down this page.
The Tolerable Upper Intake Level is the most of a nutrient per day, from food, water and supplements together, that is likely to pose no risk for almost all adults (Institute of Medicine, 2011). It does not apply under medical supervision. This page compares labels; it is not medical advice.
Sources: amounts from the DSLD label; Daily Values from 21 CFR 101.9(c)(8)(iv); adult upper limits from the Institute of Medicine's DRI summary tables (2011). How positions are computed.
Which products have the closest formulas?
6 products list the very same ingredients; the nearest amounts come first.
- Tryptophan 480 mgDr. Clark Research Association Dr. Clark Zentrum same ingredients
- L-Tryptophan 1000 mgNOW · off the market same ingredients
- L-TryptophanThorne Research · off the market same ingredients
- L-Tryptophan 500 mgCalifornia Academy of Health same ingredients
- L-TryptophanSuperSmart · off the market same ingredients
- L-Tryptophan 1000 mgAN Amazing Nutrition Amazing Formulas same ingredients
Source: ingredient lists of every product's current label in DSLD (version 9.4.0); similarity weights each shared ingredient by how rare it is.
What does the label say about taking it?
Quoted from the label as DSLD transcribed it: the maker's words, including any claim about what the product does, which the FDA has not evaluated and PlainVitamins does not endorse.
- Directions
- Suggested Usage: Take one or two 1/4 level teaspoons 2 to 3 times daily on an empty stomach, with final dose at bedtime, or as directed by your physician.
- Warnings
- Caution: For adults only.
- Consult physician if pregnant/nursing, taking medication (especially antidepressants such as SSRIs or MAOIs), or have a medical condition.
- May cause drowsiness. Do not use with alcoholic beverages or while operating heavy machinery.
- Keep out of reach of children.
- Do Not Eat Freshness Packet Enclosed.
- Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.
- Allergens and what it does not contain
- Every lot of NOW L-Tryptophan is tested to be free of Peak E and microbial contamination.
- Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients.
- Storage
- Store in a cool, dry place after opening.
Source: label statements in DSLD label 53458.
What else is on the label?
Other ingredients: Cellulose.
Seals and symbols as the label prints them (the maker's; a certifier's own list confirms a seal): GMP QUALITY ASSURED; Non-GMO.
How many labels does L-Tryptophan Powder have?
5 labels are on file under this name since October 1, 2012: other sizes, label designs and reformulations. The current one leads this page.
- Label 53458 (current) Entered November 24, 2015 · on the market · 2 oz. · UPC 7 33739 00263 1
- Label 42744 Entered February 25, 2015 · off the market October 23, 2015 · 2 oz. · UPC 7 33739 00263 1
- Label 36998 Entered October 27, 2014 · off the market February 16, 2015 · 2 oz. · UPC 7 33739 00263 1
- Label 26888 Entered November 25, 2013 · off the market July 2, 2014 · 2 oz. · UPC 7 33739 00263 1
- Label 13615 Entered October 1, 2012 · off the market June 14, 2013 · 2 oz. · UPC 7 33739 00263 1
Source: DSLD label entry and market events, version 9.4.0 (labels entered through September 25, 2025).
Who makes it?
The label names NOW Foods (manufacturer), Bloomingdale, IL. All NOW products.