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L-tryptophan and 5-Hydroxy-L-tryptophan (5-HTP)

L-Tryptophan and 5-HTP (5-Hydroxy-L-tryptophan) Supplements Reviewed By Consumerlab.com

Learn how to find the best L-Tryptophan and 5-Hydroxytryptophan (5-HTP) supplements, evidence for using L-tryptophan or 5-HTP for sleep, depression, migraine, and more. Plus, dosage, safety, side effects and potential drug interactions. Find out which L-Tryptophan and 5-Hydroxytryptophan (5-HTP) supplements passed our tests.

L-tryptophan and 5-Hydroxy-L-tryptophan (5-HTP) Review

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News Release

July 31, 2018

Best L-Tryptophan and 5-HTP Supplements Identified by ConsumerLab -- ConsumerLab Tests Strength and Purity of Supplements for Sleep and Mood

White Plains, New York, July 31, 2018 — L-tryptophan supplements are often promoted to improve sleep and 5-HTP supplements to help with depression.

Clinical Update

11/20/2011

L-Tryptophan -- Still a Problem?

A woman in Illinois taking L-tryptophan for insomnia developed the same serious problems that resulted in L-tryptophan being temporarily removed from the market several years ago. Is L-tryptophan any safer now than it was before? For more information, see the update to the L-Tryptophan and 5-HTP Review Article.

CL Answer

Which supplements and lifestyle changes improve sleep, and which cause insomnia?

Find out which vitamins may help you sleep and learn if any vitamins or supplements can cause insomnia.

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Clinical Update

8/04/2013

5-HTP Concern

Three cases of eosinophilia-myalgia syndrome (EMS) have been reported among people taking 5-HTP, a compound related to L-tryptophan. EMS is a debilitating immune condition which has occurred in people taking L-tryptophan, but there were no previous reports of it being caused by 5-HTP. Get the details in the the updated review article on L-Tryptophan and 5-HTP >>

Product Review

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Lion's Mane and Chaga Supplements Review

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Lion's Mane and Chaga Supplements tested by ConsumerLab.com

CL Answer

Which vitamins and supplements should be stopped before getting blood work and laboratory tests?

Find out which vitamins and supplements can interfere with blood, urine or stool tests, and imaginging tests. Learn how B vitamins such as biotin, niacin and riboflavin, as well as calcium supplements, St. John’s wort, vitamin C, and others supplements can affect test results, as well as common foods that may interfere with tests.

Vitamin & Supplements to Stop Before Blood Tests

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Find Out Which Protein Products Passed or Failed Our Tests

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Melatonin Supplements Review

Trouble Sleeping? See CL's Tests of Melatonin Supplements and Top Picks.

Melatonin Review 2024

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See our Top Picks for Wrinkles and Joints

CL Answer

What is the best way to take melatonin to get a good night's sleep?

Learn more about the best way to take melatonin for better sleep. When to take it, how to take it, and general melatonin information.

Melatonin Review 2024

Clinical Update

11/08/2022

5-HTP for Sleep?

A CL Member asked how to use 5-HTP to improve sleep. Find out what research suggests in the 5-HTP section of our 5-HTP and L-Tryptophan and Supplements Review.

Also see our CL Answer about supplements and lifestyle modifications for insomnia.

Clinical Update

8/24/2021

Parkinson's Disease: 5-HTP for Sleep?

Can supplementation with 5-HTP reduce sleep disturbances in people with Parkinson's disease? See what a recent study found in the What It Does section of our L-Tryptophan and 5-HTP Supplements Review.

Also see our answer to the question: Do supplements help with Parkinson's disease treatment or prevention?

Clinical Update

1/19/2019

Dog Overdoses on Supplement

Be sure to keep your supplements away from pets -- especially if they taste sweet. A dog overdosed on its owner's fast-dissolving tablets, putting it in a coma, according to a recent report. For details, see the Concerns and Cautions section of the L-tryptophan and 5-HTP Supplements Review.

CL Answer

Which supplements, foods or diet and lifestyle changes help relieve acid reflux (heartburn), and which worsen it?

Find out which supplements and foods can help relieve acid reflux, and which can make it worse.

Supplements Making Acid Reflux Worse -- Man with acid reflux pain

CL Answer

Which supplements may benefit people with essential tremor, and which should be avoided?

Learn about supplements used for treating essential tremor, including caprylic acid (also called octanoic acid), thiamin (vitamin B1), cannabidiol (CBD), GABA (gamma-aminobutyric acid), and branched-chain amino acids. Find out which work and which don't. Also find out which supplements and food may make essential tremors worse.

Man with essential tremor holding a cup with his right hand and bracing his wrist with his left hand

Product Review

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Apple Cider Vinegar Review — Bottled Liquids and Supplements

Find the Best Apple Cider Vinegar. See Which Apple Cider Vinegar Liquids and Supplements Passed Our Tests of Quality.

Apple Cider Vinegar Supplements Reviewed by ConsumerLab.com

CL Answer

What are the best supplements for depression and anxiety?

Best natural supplements for depression and anxiety, including the evidence for fish oil, vitamin D, probiotics, and herbal supplements for depression such as curcumin (from turmeric) and saffron.

Best Supplements for Depression and Anxiety -- sad young woman sitting on couch, looking toward the window

CL Answer

Do supplements help with Parkinson’s disease treatment or prevention?

Learn what has been shown with vitamins D and E, niacin, CoQ10, melatonin, creatine, SAMe, NAC, valerian, CoQ10, and CBD, as well as with coffee and the Mediterranean and MIND diets for treating and/or preventing Parkinson's disease.

Elderly man with parkinsons holding trembling hand while eating

Recalls & Warnings

February 22, 2021

FDA Warns Seller of Melatonin & Other Sleep Supplements

On February 18, 2021, the FDA issued a warning letter to SANA Group LLC following a review of the company's website, which found statements made about the company's products Sleep Sana Sleep Drops and Sleep Shots to be drug claims.

CL Answer

Does ergothioneine help prevent age-related problems such as impaired cognition, Alzheimer’s disease, Parkinson’s disease or cataract, and is it safe?

Learn about ergothioneine and its potential use for cognitive impairment, dementia, Alzheimer's disease, Parkinson's disease, cataract, or kidney disease, as well as its safety and cost of supplements containing this ingredient.

Various types of mushrooms that contain ergothioneine in a wooden bowl on a wooden countertop

Recalls & Warnings

December 01, 2018

Seller of 5-HTP, Potassium & More Warned for Manufacturing Violations

On September 7, 2018, the FDA issued a warning letter to The Delano Company, Inc.

Recalls & Warnings

December 21, 2016

Seller of 5-HTP, Chromium, Curcumin and More Warned for Drug Claims

On December 1, 2016, the FDA issued a warning letter to Aurora Health and Nutrition following a review of the company's website, which found statements made about its products, 5-HTP, Alpha Lipoic Acid, the Argentyn 23 product line, Artecin 90 Vegetarian Capsules, ...

Recalls & Warnings

July 27, 2012

Prescription and Street Drug Alternatives Found in Male Enhancement, Mood, and Sleep Supplements

On July 10, 2012, the FDA issued a warning letter to Evol Nutrition Associates, Inc. subsequent to a 2011 inspection which found a number of the company's products contained prescription and investigational drugs and were misbranded.