---
product_id: 3810651
title: "Source Naturals, L-Tryptophan 500mg - 120 Capsules"
brand: "source naturals"
price: "HK$274"
currency: HKD
in_stock: true
reviews_count: 8
category: "Source Naturals"
url: https://www.desertcart.hk/products/3810651-source-naturals-l-tryptophan-500mg-120-capsules
store_origin: HK
region: Hong Kong
---

# Supports deep, restful sleep 500mg pure L-Tryptophan per capsule Boosts immune regulation naturally Source Naturals, L-Tryptophan 500mg - 120 Capsules

**Brand:** source naturals
**Price:** HK$274
**Availability:** ✅ In Stock

## Summary

> 🌟 Unlock your best mood and sleep—because thriving never goes out of style.

## Quick Answers

- **What is this?** Source Naturals, L-Tryptophan 500mg - 120 Capsules by source naturals
- **How much does it cost?** HK$274 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.hk](https://www.desertcart.hk/products/3810651-source-naturals-l-tryptophan-500mg-120-capsules)

## Best For

- source naturals enthusiasts

## Why This Product

- Trusted source naturals brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Sleep Like a CEO:** Experience deep, restorative sleep that powers your productivity and creativity every morning.
- • **Legacy of Excellence:** Over 40 years of proven quality from Source Naturals, a brand trusted by health-conscious professionals.
- • **Clean & Trusted Formula:** Gluten-free, dairy-free, soy-free, and manufactured under strict FDA cGMP standards for peace of mind.
- • **Immunity Meets Serenity:** Harness the immune-boosting kynurenines pathway for holistic wellness beyond just mood support.
- • **Mood Mastery in a Capsule:** Elevate your serotonin levels naturally for calm, balanced days without the pharmaceutical fog.

## Overview

Source Naturals L-Tryptophan delivers 500mg of a premium essential amino acid per capsule, designed to naturally support mood balance, relaxation, and deep sleep. Backed by over four decades of trusted manufacturing under FDA cGMP standards, this gluten-free, allergen-conscious supplement also promotes immune health through kynurenine pathways. Ideal for busy professionals seeking a natural edge in mental wellness and restorative rest.

## Description

desertcart.com: Source Naturals, L-Tryptophan 500mg - 120 Capsules | Helps Support Mood, Relaxation, and Sleep : James, Tommy: Health & Household

Review: How the hell did I not know about this before? - I know that's a funny title, but seriously, how the hell did I not??? I was a child with OCD and I have been an adult with OCD and anxiety. I'm also sort of a naturalist and very anti-pharmaceutical. I don't care what anyone says, but this country is driven by "quick fixes" and "happy pills," which of course NEVER solve the problem. I can honestly say that this supplement has saved me in every way that I needed to be saved. I could not for the life of me figure out why my anxiety got worse as an adult where I started having panic attacks and then fearing that I would have panic attacks which brought on more panic attacks. I won't be a hypocrite. I have a script for Xanax but I RARELY take it. When used on occasion, it is a brilliant med, but I don't want to need to take it. I first tried 5-HTP and I'm a very happy person so when I started getting really agitated, I knew something was weird. Then, I read a bunch of reviews where you aren't supposed to drink within 6 hours of taking it and you shouldn't take Ibuprofen. So, essentially, you aren't supposed to live a real life or get cramps or headaches because just have to suffer through them. If I received major benefit from it, I would have gone ahead and taken it. After getting moody, I look again at the reviews for L-Tryptophan. I can honestly say that this has CHANGED ME! No more panic. Sleeping amazingly. I'm not stressed. I hardly have any anxiety. Where have you been all my life, L-Tryp... seriously??? I have friends that are on SSRI's AND Benzos daily and they STILL have panic attacks. If ALL of that medication isn't at least getting rid of your issues, why the hell would you continue to take it and say to yourself, "This seems very wrong..." After having anxiety daily and panic attacks often and literally beginning to question doing things because I didn't want to have panic, I knew that I needed to find SOMETHING to help me or I would literally be nuts by the time I was 40. Friends, this seriously have saved me. I have tried a LOT of stuff (I mean A LOT), but in getting to the root of my stuff (OCD/anxiety), I figured that low serotonin was the bottom line. It would seem then that raising my serotonin levels naturally would be key. I cannot say enough how amazing this product has been. I wish I could give it 10 stars and an Academy Award! Thank you, Source Naturals for making an excellent product. I will be buying a lifetime supply! UPDATE: it's over a month later and I haven't had a panic attack or taken Xanax once!! I think it's a combo of working with your thoughts as well but I really do believe in this product.
Review: Skeptical of this kind of thing, but wow... - TL;DR Version: I'm incredibly skeptical of alternative medicine, but it works. Long Version: I've been wrestling with severe PTSD for years, including depression, anxiety problems, and sleep disorders. But getting treated for PTSD is difficult and I hate the side-effects of psychiatric Rx's. Still, I've bordered on major mood problems that made me desperate for something. I was willing to check myself into an institution, except my insurance provider wouldn't cover enough of the expense. Now let me say right up front that I am a skeptic. I don't put much stock in alternative medicine, as a rule. Yeah, okay, Valerian works, opioids and certain other "herbs", but most of the effective ones are Schedule-narcs, making it irrelevant for the don't-want-to-go-to-jail type of person. But I did my research and found some medical literature supporting the use of L-Tryptophan for my symptoms, so I thought I'd give it a try. But I wasn't hoping for anything. In fact, I explicitly expected this NOT to work. Wow, I was wrong. This works so wonderfully that I wonder when the big pharma co's are going to catch on and forced the FDA to take this off the OTC market. Regimine: Three capsules (500mg) first thing in the morning on an empty stomach (this is important) Two capsules mid-day an hour before lunch. Two capsules an hour before dinner. I also take melatonin supplements before bed. This helps, but don't overdo it or it can be counter-productive. Effect: It is very subtle at first. It took me a couple of weeks before I realized that I was actually feeling fine for a change. That might not sound like a big deal, but if you're suffering with PTSD, trust me: feeling "fine" is a joy. I am able to deal with life without getting freaked out and spiraling down the rabbit hole. Things just don't upset me the way they used to. I can handle the regular life "stuff"; everything doesn't become Instant Crisis Freakout. In fact, it's rather hard for me to get upset about anything. If that sounds like heaven to you, then this is the supplement you want. When I came to my PMS week, I was worried I'd find out that I was just imagining the effect, but nope -- I made it through that week with only a slight mood swing. Nothing serious. I ran out about a month ago and didn't bother to re-up because one of the features of my PTSD that this does nothing for is the procrastination (note that; this won't fix everything). It was a week or so, and I started noticing my stress returning. In another week, it was bad again, so I bought a new bottle. It's been a week, and I'm feeling good again. People seem to take this for a lot of reasons, and I can't speak to any other than anxiety and depression. It did not do anything for my insomnia directly. It was more of an indirect effect of making me chill enough that I wasn't going to sleep rigid with worry. Still, it doesn't put me out or anything. For that, I use the melatonin. Note: If you're trying to make up your mind whether to take this or 5-HTP, go with this. It's the precursor for the stuff in 5-HTP, and works a lot better. You might try combining this with Emergen-C (not just regular Vitamin C capsules) and a B-6 liquid supplement for even better effects. I noticed a difference with those, but YMMV. All in all, I'm very happy with this.

## Features

- The essential amino acid l-tryptophan helps support relaxation, restful sleep, and positive mood.*
- l-Tryptophan also supports immune functions because it is the body’s precursor to the kynurenines that regulate immunity.
- Suggested Use: 1 capsule three times daily, between meals and preferably with fruit juice. To support restful sleep, take an additional 3 capsules before bed.*
- Over 40 Years of Trust. Source Naturals was created in 1982 by CEO Ira Goldberg to support everyone’s potential to enjoy optimal health.
- Manufactured under the Good Manufacturing Practices (cGMPs) established by the US Food and Drug Administration (FDA).

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B000GFSVS2 |
| Age Range Description | Adult |
| Allergen Information | Dairy Free, Egg Free, Gluten Free, Soy Free, Wheat Free |
| Best Sellers Rank | #32,491 in Health & Household ( See Top 100 in Health & Household ) #338 in Herbal & Nutritional Sleep Supplements #2,119 in Sales & Deals |
| Brand | Source Naturals |
| Brand Name | Source Naturals |
| Color | No Color |
| Container Type | Bottle |
| Customer Reviews | 4.5 out of 5 stars 1,948 Reviews |
| Diet Type | Gluten Free |
| Dosage Form | Capsule |
| Flavor | Unflavored |
| Global Trade Identification Number | 00021078019855 |
| Item Dimensions | 2.51 x 2.51 x 4.6 inches |
| Item Form | Capsule |
| Item Weight | 1.6 ounces |
| Manufacturer | Threshold Enterprises |
| Manufacturer Part Number | SN1985 |
| Material Features | No Artificial Colors |
| Material Type Free | Egg Free, Soy Free, Yeast Free, wheat Free |
| Model Name | SN1985 |
| Model Number | SN1985 |
| Number of Items | 1 |
| Primary Supplement Type | L-Tryptophan |
| Product Benefits | Sleep Support |
| Special Ingredients | L-Tryptophan |
| Specific Uses For Product | relaxation, rest, sleep support |
| Supplement Formulation | Individual Supplement |
| Total Servings Per Container | 40 |
| UPC | 021078019855 |
| Unit Count | 120 Count |
| Warranty Description | Please see manufacturer's label for instruction |

## Product Details

- **Brand:** Source Naturals
- **Diet Type:** Gluten Free
- **Flavor:** Unflavored
- **Item Form:** Capsule
- **Item Weight:** 1.6 ounces
- **Item dimensions L x W x H:** 2.51 x 2.51 x 4.6 inches
- **Primary Supplement Type:** L-Tryptophan
- **Product Benefits:** Sleep Support
- **Special Ingredients:** L-Tryptophan
- **Unit Count:** 120.0 Count

## Images

![Source Naturals, L-Tryptophan 500mg - 120 Capsules - Image 1](https://m.media-amazon.com/images/I/71VMT7Lk+EL.jpg)
![Source Naturals, L-Tryptophan 500mg - 120 Capsules - Image 2](https://m.media-amazon.com/images/I/81hWjFJLy3L.jpg)
![Source Naturals, L-Tryptophan 500mg - 120 Capsules - Image 3](https://m.media-amazon.com/images/I/71JhWv4-4qL.jpg)
![Source Naturals, L-Tryptophan 500mg - 120 Capsules - Image 4](https://m.media-amazon.com/images/I/71EdCYlMBVL.jpg)
![Source Naturals, L-Tryptophan 500mg - 120 Capsules - Image 5](https://m.media-amazon.com/images/I/71QVOtkcFVL.jpg)

## Available Options

This product comes in different **Size, Item Package Quantity** options.

## Questions & Answers

**Q: How many milligrams per tablet?**
A: 500mg each.  I typically only need 1.  Remember these tips for use.  This is a protein precursor so you will not show much affect if you have eaten protein recently.  Eat dinner a few hours before bed, and take the Tryptophan about 30 minutes before you need to sleep.  This like all amino acids function much better when you add a B-Vitamin complex to it as a transport mechanism.

**Q: Why is their no indication of the source of this tryptophan? Where does it come from?**
A: I need to know the source also.  I had been taking 5-HTP, but my body can't tolerate it.  5-HTP is made from an African legume, and I've noticed that legumes cause fibro-like inflammation in my muscles. (My father had gout.  I don't have the gout, but I can't tolerate anything derived from a bean.)   From time to time, I have had problems with certain supplements.    Knowing the source before I buy is a necessary thing for me also.

**Q: What is listed as "other ingredients"?**
A: Other Ingredients: gelatin (capsule), dibasic calcium phosphate, mycrocrystaline cellulose, silica, and magnesium stearate.  Also, listed with the L-Tryptophan is Iron (naturally occurring) 575 mcg which it indicates is 3%DV of daily need.  But the DV is according to the FDA I'm sure.  After my husband passed away, I found some of this in his things.  I took some and found it helped me get through this and also get sleep at night.

**Q: What is the source of the dextrose used for this tryptophane? Is it made in China?**
A: As you can see from the company, their ingredients are sourced from China. Kudos to them for being honest.  Unfortunately, beets and corn, especially from China, are GMO. No thanks. The search for a company that puts consumer health over profit goes on!

## Customer Reviews

### ⭐⭐⭐⭐⭐ How the hell did I not know about this before?
*by K***. on January 30, 2014*

I know that's a funny title, but seriously, how the hell did I not??? I was a child with OCD and I have been an adult with OCD and anxiety. I'm also sort of a naturalist and very anti-pharmaceutical. I don't care what anyone says, but this country is driven by "quick fixes" and "happy pills," which of course NEVER solve the problem. I can honestly say that this supplement has saved me in every way that I needed to be saved. I could not for the life of me figure out why my anxiety got worse as an adult where I started having panic attacks and then fearing that I would have panic attacks which brought on more panic attacks. I won't be a hypocrite. I have a script for Xanax but I RARELY take it. When used on occasion, it is a brilliant med, but I don't want to need to take it. I first tried 5-HTP and I'm a very happy person so when I started getting really agitated, I knew something was weird. Then, I read a bunch of reviews where you aren't supposed to drink within 6 hours of taking it and you shouldn't take Ibuprofen. So, essentially, you aren't supposed to live a real life or get cramps or headaches because just have to suffer through them. If I received major benefit from it, I would have gone ahead and taken it. After getting moody, I look again at the reviews for L-Tryptophan. I can honestly say that this has CHANGED ME! No more panic. Sleeping amazingly. I'm not stressed. I hardly have any anxiety. Where have you been all my life, L-Tryp... seriously??? I have friends that are on SSRI's AND Benzos daily and they STILL have panic attacks. If ALL of that medication isn't at least getting rid of your issues, why the hell would you continue to take it and say to yourself, "This seems very wrong..." After having anxiety daily and panic attacks often and literally beginning to question doing things because I didn't want to have panic, I knew that I needed to find SOMETHING to help me or I would literally be nuts by the time I was 40. Friends, this seriously have saved me. I have tried a LOT of stuff (I mean A LOT), but in getting to the root of my stuff (OCD/anxiety), I figured that low serotonin was the bottom line. It would seem then that raising my serotonin levels naturally would be key. I cannot say enough how amazing this product has been. I wish I could give it 10 stars and an Academy Award! Thank you, Source Naturals for making an excellent product. I will be buying a lifetime supply! UPDATE: it's over a month later and I haven't had a panic attack or taken Xanax once!! I think it's a combo of working with your thoughts as well but I really do believe in this product.

### ⭐⭐⭐⭐⭐ Skeptical of this kind of thing, but wow...
*by H***E on July 12, 2011*

TL;DR Version: I'm incredibly skeptical of alternative medicine, but it works. Long Version: I've been wrestling with severe PTSD for years, including depression, anxiety problems, and sleep disorders. But getting treated for PTSD is difficult and I hate the side-effects of psychiatric Rx's. Still, I've bordered on major mood problems that made me desperate for something. I was willing to check myself into an institution, except my insurance provider wouldn't cover enough of the expense. Now let me say right up front that I am a skeptic. I don't put much stock in alternative medicine, as a rule. Yeah, okay, Valerian works, opioids and certain other "herbs", but most of the effective ones are Schedule-narcs, making it irrelevant for the don't-want-to-go-to-jail type of person. But I did my research and found some medical literature supporting the use of L-Tryptophan for my symptoms, so I thought I'd give it a try. But I wasn't hoping for anything. In fact, I explicitly expected this NOT to work. Wow, I was wrong. This works so wonderfully that I wonder when the big pharma co's are going to catch on and forced the FDA to take this off the OTC market. Regimine: Three capsules (500mg) first thing in the morning on an empty stomach (this is important) Two capsules mid-day an hour before lunch. Two capsules an hour before dinner. I also take melatonin supplements before bed. This helps, but don't overdo it or it can be counter-productive. Effect: It is very subtle at first. It took me a couple of weeks before I realized that I was actually feeling fine for a change. That might not sound like a big deal, but if you're suffering with PTSD, trust me: feeling "fine" is a joy. I am able to deal with life without getting freaked out and spiraling down the rabbit hole. Things just don't upset me the way they used to. I can handle the regular life "stuff"; everything doesn't become Instant Crisis Freakout. In fact, it's rather hard for me to get upset about anything. If that sounds like heaven to you, then this is the supplement you want. When I came to my PMS week, I was worried I'd find out that I was just imagining the effect, but nope -- I made it through that week with only a slight mood swing. Nothing serious. I ran out about a month ago and didn't bother to re-up because one of the features of my PTSD that this does nothing for is the procrastination (note that; this won't fix everything). It was a week or so, and I started noticing my stress returning. In another week, it was bad again, so I bought a new bottle. It's been a week, and I'm feeling good again. People seem to take this for a lot of reasons, and I can't speak to any other than anxiety and depression. It did not do anything for my insomnia directly. It was more of an indirect effect of making me chill enough that I wasn't going to sleep rigid with worry. Still, it doesn't put me out or anything. For that, I use the melatonin. Note: If you're trying to make up your mind whether to take this or 5-HTP, go with this. It's the precursor for the stuff in 5-HTP, and works a lot better. You might try combining this with Emergen-C (not just regular Vitamin C capsules) and a B-6 liquid supplement for even better effects. I noticed a difference with those, but YMMV. All in all, I'm very happy with this.

### ⭐⭐⭐⭐⭐ So Far Works Great!!
*by P***M on January 10, 2014*

First I need to mention I have trouble sleeping. Not so much falling asleep but waking up in the middle of the night numerous time either having to go to the bathroom or just not being able to fall back to sleep. I also have numerous medical issues going on. I've been using Benedryl which works good but it raised my blood pressure and blood glucose levels so I had to stop taking it. I am on way too many other medicines to be put on sleeping pills so now I didn't know what to do. I averaged about fours hours of sleep per night. Then I found these L-Tryptophan capsules on Amazon.com. I figured what the heck and decided to purchased them. The first two nights i took three pills and I slept seven hours (did wake up once to use the bathroom but fell right back to sleep). Last night I decided to take four pills and slept eight hours through the night and didn't even wake up to use the bathroom. Wow, did I feel good this morning. I was also told to take a small dose of Melatonin with this pill and I'd sleep like a baby. However, have not tried yet. I was also told that it takes about two weeks for this to really kick in as it settles into your system. I would highly recommend this product as you can see what its done for me the first three nights. Well worth the money! I will review again in a couple of week to let you know the progress. Thank you Soure Naturals and Amazon. UPDATE 2/8/2014 - I've been using L-Tryptophan for about a month now and wow, 7-8 hours of solid sleep per night. For me, four pills before bedtime does the trick. I have not used during the day for anxiety but in three weeks will be taking an international flight and I'm afraid to fly so will take one of these before boarding the plane to see if it reduces the fear. But I have to say, sleeping so good at night and waking up feeling rested is so well worth the money for this product.

## Frequently Bought Together

- Source Naturals L-Tryptophan, for Mood, Relaxation, and Sleep*, 500mg - 120 Capsules
- NOW Supplements, NAC (N-Acetyl Cysteine) 600 mg with Selenium, 250 Veg Capsules
- NOW Foods Supplements, L-Tyrosine 500 mg, Supports Mental Alertness*, Neurotransmitter Support*, 120 Capsules

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*Product available on Desertcart Hong Kong*
*Store origin: HK*
*Last updated: 2026-08-23*