We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is Glucosamine?

By Sherry Holetzky
Updated Feb 29, 2024
Our promise to you
WiseGeek is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WiseGeek, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Glucosamine is an amino sugar compound produced by the body. Though it is common in the liver and kidneys, it is most often found in cartilage. Glucosamine is derived from glucose molecules and is believed to aid in repairing damaged cartilage, building new cartilage, cushioning joints, relieving pain, and reducing inflammation.

Glucosamine is also the name given to the dietary supplement created through extracting amino sugars from the tissues of shellfish such as crab and lobster. There are also glucosamine sulfates, which are synthetically produced salts derived from naturally occurring glucosamine. These salts are sometimes combined with chondroitin sulfates to aid in the relief of arthritis and other painful conditions affecting the joints, ligaments, and tendons. Sulfates may not be as potent as extracted glucosamine.

Current data indicates that patients who take these supplements experience pain relief and reduced inflammation at about the same level as that which is achieved through taking non-steroidal anti-inflammatory medications, or NSAIDS, such as aspirin and ibuprofen. There is also a liquid form of this supplement available for those whom have difficulty swallowing pills.

Although glucosamine may have fewer side effects than NSAIDS for most patients, people who suffer from diabetes should be especially careful when taking this supplement since it is derived from glucose. It is wise to speak to a doctor before use and to check blood sugar more frequently during use.

People who are allergic to shellfish should take care when using this product, although shellfish allergies usually indicate that a person is allergic to the proteins found in shellfish. The substance is extracted from a carbohydrate rather than a protein, but allergy sufferers should still consult with a health care provider before taking it, as should pregnant and nursing women. This supplement is not recommended for children.

Glucosamine is labeled as a food supplement and therefore the amount and purity of glucosamine in such products is not regulated by the Food and Drug Administration. Before choosing a supplement, compare the concentration in similar products or ask your pharmacist to assist you in selecting a supplement. Choose a well-known, well-established brand name that guarantees its products.

Always consult with your health care provider before beginning a supplement regimen, and make sure the supplement will not adversely interact with current medications.

WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

By laurier — On Oct 21, 2015

I'm so glad I read the above comments. I recently adopted a 10-year-old lab retriever. I am familiar with joint issues, arthritis, spine issues, etc. from my previous shepherd mix. I thought nothing about starting Charlie on glucosamine because it is so common with people and dogs. But I gave Charlie the three pills yesterday for his size and within six hours he had diarrhea. All day today he hasn't been eating or drinking and has had diarrhea. He was trying to eat grass and he did vomit a little, mostly clear liquid. I am letting him sleep and take it easy which is what he wants to do. I am stopping the glucosamine immediately. I will find something else for him. Maybe just some type of aspirin. Thank you to the people above for posting. I have posted my experience in the hope that it also helps someone.

By anon927009 — On Jan 21, 2014

Bottom line: Do your own research or talk to a pharmacist who is willing to do the research for you. I glanced at this site while doing research (I'm having difficulty finding synthetic glucosamine in articles) and the fact that there isn't even a reference on this page should be alarming to anyone.

Diabetics should be careful taking this because it is related to Glucose (it is an amino derivative, hence Glucosamine). To be fair, studies are all over the place when it comes to glucosamine and chondroiton, and this page could just as easily site resources to support their argument as I could to support mine. Bottom line, it's effectiveness is a topic of debate and ongoing research. The RCT's I have read recently show that placebo was almost as effective in improving pain symptoms as expressed by the patient.

Also, for those who believe they have lost their dogs to this supplement, I don't know whether this would be the cause but I want to remind everyone that a vet should be about the only person to recommend something for your pet. As for us humans, please see your local pharmacist or family physician in addition to your own research. --A Pharmacy Student

By anon289553 — On Sep 04, 2012

My dog has been on Missing Link for Joint Health which has glucosamine in it and she is thriving. Her hips are much better and she's more playful. Perhaps the dosage has been incorrect for some of your pets and it might be better to have let them taken it in conjunction with other healing elements.

By anon264079 — On Apr 26, 2012

I think glucosamine killed my dog too. I've been searching the net and am seeing a recurrence of quite a few dogs getting ill from glucosamine supplements. My vet said it was safe when I told him it was the one supplement I was giving him. If your dog gets sick one time, please stop! Some dogs are very sensitive to it. Beware!

By anon168753 — On Apr 18, 2011

I had very bad joint pain in my hands for over five years now and I'm only 25. I have been taking Glucosamine Chondroitin and MSM pills for a about three weeks now which I bought from Vitacost online. It has worked perfect for me, my pain is gone and I have very little stiffness. I have also given some to my mother who is over 50 to start taking as her joints were hurting her all over her body, and she can tell the difference as well. The brand I bought is NSI.

I would pay a thousand dollars for these pills because I have tried everything else with no results. hope this helps someone!

By anon151588 — On Feb 10, 2011

If glucosamine sulfate is a salt, why can diabetics not take it?

By anon68528 — On Mar 03, 2010

This is all very confusing. This page explains what glucosamine is and its benefits are; however, I read another article explaining that glucosamine was proven not to work at all by a study carried out by University of Utah researchers (if I'm not mistaken). Does it work or not? And if it doesn't, why does this page still show this misleading information?

By anon47401 — On Oct 04, 2009

Well, I am no. 6. My dog died yesterday. One day after I posted my question. I will never give a dog Glucosamine again!

By anon47233 — On Oct 02, 2009

I know the Glucosamine is causing the same symptoms in my dog. She has arthritis and the vet told me to give her 500 mg of Glucosamine a day. I could only get 250 mg in her each day. She started getting very sick to her stomach. (loose stools and vomiting) Her legs got worse. More stiff and weak. The vet gave her Prednisone and it helped. I thought I could give her the Glucosamine again. One dose and she is so sick again, she can't stop vomiting. She can hardly walk at all. My vet said it is very rare, but she can't tolerate it. It has been two days, and she is not getting better. Does anyone know how long it stays in the system? Thanks

By anon20537 — On Nov 02, 2008

You need to take your dog to a veterinarian immediately- it seems extremely unlikely all of those symptoms, especially soreness and inability to walk, are due to a megadose of glucosamine.-vet tech jon

By anon15326 — On Jul 08, 2008

Glucosamine overdose will typically cause

mild gastrointestinal problems in some sensitive individuals, but the side-effects are reversible and will disappear upon discontinuing use. People with peptic ulcers and those taking diuretics are more likely to experience gastrointestinal discomfort than others. People who are allergic to shellfish (it is derived from the shells) should not take glucosamine supplements derived from shrimp, crabs or lobsters. You can find synthetic glucosamine if you have allergies.

By Dayton — On May 29, 2007


Though I don't know anything about harmful side effects of too much glucosamine, I highly recommend taking your dog to the vet. With symptoms like that, I wouldn't spend too much time wondering...

Best of luck!

By anon1392 — On May 28, 2007

okay the pharmasisit in my town told me to give my dog only one pill a day, just regular glucosamine, now what i am wondering, is how much would it take to make a dog sick, my dog has been really sick and i think that my foster kid could be giving her too much, how many pills do you think it would take, and how long do you think it could take for her to pass on, if this kid is killing my dog i want to be able to do somehting about it, i have hid the glucosamine.. some of the side effects that she has been having are puking, diarea, soreness, not being able to climb stairs, and not being able to get up off of her belly. thank you soo much for your time!!

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.