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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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CL Answer

I take fluoxetine (Prozac), a SSRI drug to treat depression. Are there supplements I should avoid, or be taking, due to this drug?

Learn about Prozac (fluoxetine) drug interactions along with other supplements and SSRIs.

Woman Taking Pill with Glass of Water

CL Answer

Can any supplements improve or worsen symptoms of fibromyalgia?

Find out if any supplements may help improve fibromyalgia symptoms, learn which supplements do not seem beneficial, and find out if any supplements worsen symptoms.

Woman holding sore back

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 >>

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.

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

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?

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

Which supplements can cause diarrhea?

Can supplements like magnesium cause diarrhea? Find out which supplements may cause diarrhea, such as vitamin B12, curcumin, magnesium, vitamin C and fish oil.

Which supplements can cause diarrhea? -- Woman with gastrointestinal pain

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.

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.

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 vitamins and supplements should be stopped before getting blood work, laboratory tests, or medical imaging?

Find out which vitamins and supplements can interfere with blood, urine or stool tests, and imaginging tests, like bone scans and MRIs. 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

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.

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 26, 2012

Seller of Blood Sugar, Depression and Sleep Supplements Warned For Making Drug Claims

On October 15, 2012, the FDA issued a warning letter to BioNeurix Corporation after statements found on the company's website, http://www.pharma-tree.com, were found to promote the dietary supplements Blood Sugar 360, Amoryn, Seredyn, and Mellodyn as drugs.

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.

Recalls & Warnings

December 11, 2020

FDA Warns Seller of Curcumin and Cholesterol Supplements

On November 20, 2020, the FDA issued a warning letter to Natures Boost LLC following a review of the company's websites, which found statements made about the company's products Blood Boost Formula and Turmeric Curcumin to be drug claims.

Recalls & Warnings

December 12, 2018

Seller of Protein Powder, Spirulina & Other Products Warned for Manufacturing Violations

On October 31, 2018, the FDA issued a warning letter to DynaPro International, Inc.

Recalls & Warnings

December 05, 2018

Seller of Cold and Flu Supplements, "SuperFood" & More Warned by FDA

On October 30, 2018, the FDA issued a warning letter to American Botanical Pharmacy following a review of the company's website (www.herbdoc.com) and Facebook page, which found statements made about some of its products to be drug claims.

Recalls & Warnings

October 08, 2019

Seller of Tea, Colloidal Silver, Homeopathic Products Warned for Manufacturing Violations

On September 12, 2019, the FDA issued a warning letter to Herbal Healer Academy, Inc.

Recalls & Warnings

November 21, 2015

FTC Charges Maker of Supplement for Opiate Addiction with Deceptive Claims

On November 16, 2015, the FTC filed a lawsuit against Sunrise Nutraceuticals, LLC, charging that the company made deceptive claims its product, Elimidrol, can alleviate opiate withdrawal symptoms and increase a user's likelihood of overcoming opiate addiction. 

Recalls & Warnings

August 20, 2019

Seller of Liposomal Curcumin, Vitamin C & Melatonin Warned for Manufacturing Violations

On August 6, 2019, the FDA issued a warning letter to Let's Talk Health, Inc.

Recalls & Warnings

March 30, 2019

FDA Warns Seller of Reishi, Joint Supplements, Ginseng & More for Pesticides, Other Violations

On March 12, 2019, the FDA issued a warning letter to Yanqing "Michael" Li and Chang Su, owners of the website http://www.woohoonatural.

Recalls & Warnings

February 10, 2018

Warning to D-Limonene, Vitamin C Seller

On January 31, 2018 the FDA issued a warning letter to Long Life Unlimited, LLC following a review of the company's website which found promotional statements and testimonials made about products including Balance 600, D-Limonene, Rapha Remedy, Rapha Remedy w/ p73 Wild Oregano, Vitamin C, ...

Recalls & Warnings

December 26, 2017

Seller of BrainAlert Warned for Manufacturing Violations, Drug Claims

On December 14, 2017, the FDA issued a warning letter to BrainAlert, LLC.

Recalls & Warnings

December 26, 2017

Seller of Fish Oil, Vitamin D, Whey Protein and More Warned for Manufacturing Violations

On December 19, 2017, the FDA issued a warning letter to Maine Natural Health, Inc.

Recalls & Warnings

December 23, 2017

Seller of Meal Replacement, Protein Drinks, Cranberry and More Warned for Manufacturing Violations

On July 6, 2017, the FDA issued a warning letter to Professional Botanicals, Inc.

Recalls & Warnings

December 20, 2017

Seller of Supplements for Pain and Allergies Warned for Manufacturing Violations, Drug Claims

On December 13, 2017, the FDA issued a warning letter to GnuPharma Corporation, following a facility inspection which found a number of the company's products, including Relief capsules, Foundation capsules, Aller-geez capsules, Fit capsules, Aller-Geez Tea, Foundation herbal tea and ...

Recalls & Warnings

February 15, 2013

Energy Drink Recalled Due To Bacterial Contamination

On December 21, 2012, NBTY issued a voluntary recall of the energy supplement MET-Rx Extreme Thermo Rage Watermelon 8 fl. oz. (Manufactured by MET-Rx Nutrition, Inc.) due to bacterial contamination.

Recalls & Warnings

May 14, 2014

Maker of Mood, Smoking Cessation Supplements and More Warned for Violations, Drug Claims

On April 17, 2014, the FDA issued a warning letter to CDJ Holding, Incorporated, d.b.a.

Recalls & Warnings

September 07, 2002

FDA Sends Warning Letters to Seven Online Supplement Sellers For Therapeutic Claims

On August 27, 2002, the FDA posted seven "Cyber" letters recently issued from its Center for Food Safety and Applied Nutrition (CFSAN) to internet website operators promoting dietary supplement products that claim to diagnose, mitigate, treat, cure, or prevent a specific disease or class of ...

Recalls & Warnings

November 12, 2017

Weight Loss and Cleanse Supplements Contain Adulterated and Improperly Labeled Ingredients, FDA Warns

On November 2, 2017, the FDA issued a warning letter to Create-A-Pack Foods, Inc.

Recalls & Warnings

September 26, 2017

FDA Warns Seller of DHEA, Creatine, Chromium & More for Manufacturing Violations, Drug Claims

On August 25, 2017, the FDA issued a warning letter to Mega-Pro Nutrition, Inc., following inspections of the facility and website www.mega-pro.

Recalls & Warnings

June 07, 2017

FDA Warns Seller of Probiotic and Omega-3 Supplements for Manufacturing Violations

On May 22, 2017, the FDA issued a warning letter to BioTE Medical, LLC following a facility inspection which found its products, including BioTE DIM, BiotTE Probiotic, BioTE Iodine Plus, and BioTE Omega 3 to be adulterated because they were prepared, packed, or held under ...

Recalls & Warnings

June 06, 2017

Seller of Vision, Cholesterol, Prostate Supplements and More Warned for Drug Claims

On May 25, 2017, the FDA issued a warning letter to Herbal Doctor Remedies following a facility inspection and review of the company's websites, www.herb-doc.com, www.ChinaSecretMed.com and www.theraherb.

Recalls & Warnings

February 14, 2017

Life Extension Warned for Drug Claims

On February 1, 2017, the FDA issued a warning letter to Life Extension Foundation Buyers Club, Inc.

Recalls & Warnings

January 21, 2017

Seller of "Cancer Kits," Alpha Lipoic Acid Supplements and More Warned for Drug Claims

On December 22, 2016, the FDA issued a warning letter to Northern Health Products, Inc. following a review of the company's websites, www.northernhealthproducts.com and www.petdca.

Recalls & Warnings

January 17, 2017

Seller of Heart, Senior and Teen Supplements Warned For Drug Claims

On December 7, 2016, the FDA issued a warning letter to Esteem Products Ltd following a review of the company's website, which found statements made about its products, Cardio Life, Total Man, Total Woman, Senior Total Man, Senior Total Woman , and Total Teen to be drug ...