Glucosamine for Dogs: What to Expect From an Overdose



Hello everyone, and welcome to this guest post written by Erin Amanda. Erin is a Certified Veterinary Technician with experience in veterinary toxicology, living in Illinois with her partner, her son, and her zoo of critters.  She has written and published peer-reviewed continuing education articles on toxicology through the NAVTA journal and the VSPN network.

Arthritis and joint pain are both common ailments for an aging or elderly pet. Even with so many treatment options available, one recommendation is universally popular: glucosamine for dogs. Chances are high that if you’re the owner of an older dog, you’re also the owner of some sort of joint supplement.

There are so many products available on the market, it seems like a simple task to just pick one up at the grocery store, or even share your own joint supplement with pooch! But is this the best thing for your dog?

When we think of an overdose, we get a mental picture of our pets standing over a wartorn kitchen, the dessicated remains of a pill bottle between their feet and an appropriately guilty look on their face. Once we’ve determined what to do and gotten treatment, we can look back and laugh with relief and a little bit of dog shaming.
What we don’t take into consideration is that our human supplements contain ingredients in different doses, and other active ingredients that are safe for humans, but are toxic to dogs. Just to name a few (this is not a comprehensive list by any means):

  • Xylitol (an artificial sweetener)
  • Too much vitamin D3
  • Too much iron
  • Too much selenium
  • Caffeine
  • 5-HTP
  • Ma Huang
  • Guarana

Add in the fact that human vitamins and supplement qualities are highly variable, nor are they regulated by the FDA – the result is a dangerous combination. Always consult your vet before choosing any supplement for your pet, and stick with the recommended brands.

Seeing as glucosamine for dogs tends to come in delectable, chewy treats and tablets, they are of the utmost appeal to any dog. Your dog’s sense of smell is so strong, he can smell the treats that are covered in plastic and stowed away in a cabinet or drawer. If they manage to get their paws on a bag of their own supplements, the temptation to eat the whole thing may be irresistable. In smaller ingestions, this might not be as big of a deal. But when pooch eats an entire month’s supply, this could have a significant impact on your pet’s health.

More recent studies of glucosamine overdose has shown that while smaller ingestions only cause mild vomiting and diarrhea, large ingestions of glucosamine combined with chondroitin may potentially cause damage to the liver, and should be taken seriously.

So, what do you do if your dogs gets into a bag of glucosamine? Should you induce vomiting? Do you need to rush to the ER? That’s all going to depend on your dog.

Treatments for an overdose of glucosamine is going to vary based on the health of your dog, their age, their breed, and the dose your dog consumed. Your vet may be comfortable having you monitor for mild vomiting at home. In more severe cases, they may wish you to come into the clinic ASAP to try and get the treats back. Call your vet or one of the poison control centers before you act, and be prepared to head to a local emergency clinic if needed.

Most importantly, the key to keeping your dog safe is through preventing exposure. Keep those chews completely out of his reach. The top of the fridge, upper cabinets with doors, or other areas far beyond her reach are ideal. Remember, a closed door does not deter a determined dog.

Glucosamine for Dogs: What to Expect From an Overdose

You May Also Like

45 thoughts on “Glucosamine for Dogs: What to Expect From an Overdose

  1. We don’t think on this enough. What is safe for us is toxic to dogs. Great tips on where to store meds so your dog doesn’t get at them. You can’t be cautious enough. What a tragedy it would be have your dog get sick and possibly die because of pure forgetfulness. Thanks for this Erin:)

    1. Hi Peter, Just like you take care to keep certain products out of childrens’ reach, the same goes for your dog. So many tragedies could be prevented if we took some time to think. It’s also important to either give your dog medication made specifically for them, or if you are buying human grade (which you often can do, like with Milk Thistle as one example), you must speak to your vet to get the proper dosage. I hope this article gets people thinking.

      1. I’m dealing with this right now. Diarreah. Dehydration. Minor vomit from drinking too much too fast. Trying boiled chicken and White rice. 2 parts rice 1 part chicken breast. Skinless. Recommended for a dog with an upset tummy. One cup. His usual dog food serving.

        1. Have you taken your dog to the vet? Diarrhea, dehydration and vomiting are all very dangerous symptoms that should not be treated on your own. It sounds like a lot more than just an “upset tummy.”

  2. Hi Erin,

    You mentioned a few ingredients which are poisonous for dogs. I understand that chocolate might also prove dangerous for dogs.
    I wanted to ask if that is true, and if so why is that?

    1. Hi Ido, Hindy here. Yes chocolate is very dangerous for dogs. The toxic component of chocolate is theobromine, which is easily metabolised in humans, but not in dogs. Because it takes longer in dogs, it can build up to toxic levels. A tiny piece eaten by a big dog shouldn’t cause serious problems, but a tiny dog eating a big box of chocolates… The safest thing to do is to keep any size dog away from any size piece of chocolate. If you suspect your dog may have eaten chocolate, call the poison control centre and your vet.

    2. Hey Ido!

      What Hindy said is very true, and she covered it very well. Theobromine and caffeine are stimulants, so when dogs eat a toxic dose, they become overstimulated. This leads to changes in heart rate, tremors, and seizures.

  3. Hi Erin (and Hindy),
    You mentioned that a small amount of glucosamine would induce vomiting and diarrhea. When my dog has vomited in the past and not consumed any drugs left around I just assumed that he ate something outside that he wasn’t suppose to.

    I was wondering what side effects I would see in my dog if it ingested a large amount of glucosamine? I am just curious, as sometimes it may not be evident that the dog ingested it. And what is chondroitin?

    Thanks for the informative post!

    1. Hi there Dinh!

      “Small amounts” would be more equivalent to a dog who ingested more than their daily recommended dose, but not the contents of an entire bag. recommended daily dose of glucosamine for a dog should not cause any noticeable signs.

      Usually when we have these large ingestions, we have a dog who has gotten into an owner’s supplements or his own bag of glucosamine treats, and we find the evidence of the bottle or the bag on the floor. This is when we get worried about liver damage (which tends to initially present itself as tummy upset). If we don’t have evidence like a bottle or a bag and they are very sick, sometimes we’re not able to narrow down what caused the signs.

      Chondroitin is something that you find frequently in conjunction with glucosamine in supplements. It exists naturally in the connective tissues of the body, but they stick it into a lot of the joint supplements as well.

  4. Geez this is scary to think what your dog can get into! I never paid so much attention before until I came across your website… I never would have thought of my dog chowing all the glucosamine and whether this would be a problem or not.

    1. Hi Lynne, I know what you mean, I probably wouldn’t either except that I had a cat who threw a bottle of vitamins on the floor, it cracked and his brother ate them. Started foaming at the mouth, I rushed him to the vet and he was fine but it had never happened before so you figure a closed plastic bottle should be fine!

    2. Dogs are chewers! They love to eat absolutely anything. They make glucosamine so darned tasty like treats, it tends to be one of the first things they go for! :O

  5. Hello Hindy and Erin,
    Thanks for this information. It is really something all dog owners should be aware of. I have to admit that while I give my dog a lot of love I don’t take the time to learn what I should about keeping her as safe as I do for my grandchildren.

    My dog, China has been with me ever since she was weened from her mom. In March 2016 she will have been with us for 12 years. Yes, I have seen some aging aspects going on for her. She has arthritis and some joint problems, but she is a champ and is doing well right now.

    I would like some clarification on a habit she seems to have. When I was a kid my Dad told me that our dog ate grass because she had an upset stomach and the grass helped her. However, China’s vet told me that she throws up because she is eating the grass, It worries me sometimes because she throws up large piles of grass. Should I be worried about that?

    Thanks for this information. It was very helpful.


    1. Hey there Verna! Grass by itself is generally harmless. The theory currently is that dogs eat grass to assist them in vomiting. It’s like a chicken/egg situation where we’re not sure if the nausea or the grass eating comes first, but the end result is that it irritates their belly and helps them vomit. That is possibly even their end goal in eating it – to help get rid of something irritating their tummies.

      Now, since you know she’s a grass eater, take care when putting fertilizers or herbicidal/pesticidal products out on your lawn. By and large, these are harmless after they’ve dried and sunk into the root of the grass, but a dog eating freshly sprayed grass could potentially cause some problems..

      Since she is 12, I would also make sure that she gets a general checkup and blood work done. If she’s vomiting grass pretty frequently, sometimes it can be an indication of another disease that is making them feel sick to their stomachs, leading them to eat grass. It’s important to rule out those possibilities when you see a surge in a behavior like grass vomiting.

      Good luck and kisses to your senior!

  6. Awesome post Erin! Hindy, good collaboration!
    I did not know that some ingredients such as glucosamine could be dangerous for dogs if ingested in high quantities. I would not have thought about it but it is a very good idea to keep them high and out of reach.
    It reminds me that a friend of mine has 2 chocolate Labradors. One is like a little devil…..My friend bought a bag of mini-chocolates and without thinking left it in her car while she ran a quick errand. Well 5 minutes later, her dog had eaten 12 of them….Rushed trip to the vet followed to induce vomiting…

    1. Thanks Emily, and Erin will respond shortly. One of my dogs (not Red our other dog Jack) will just stand around us, and wait for some crumb to fall on the floor. Heaven forbid you take the garbage bin out and change the bag, he’s right there. The other day I was at the vet (what else is new), and this woman was there with her dog. A few days before he had eaten a huge tub of chocolates, he had to be rushed to the vet for treatment. I keep everything out of the dog’s reach – headphone wires, rubber bands, plastic bags, cleaning products… anything they could get their paws on.

    2. Dogs sure do love those chocolates! We’ve fielded calls at the center from dogs who chew THROUGH the cabinet wood to get to chocolate inside a tupperware container. Their noses are amazing!

      I just wish they weren’t so fond of sweet-tasting treats! They’re almost always bad for them!

        1. A lot of it is personal taste. In my experience, they don’t tend to be as fond of the carob treats as they are of actual chocolate.

          Though when my cat lays a chocolate-looking treat in the litterbox, my dog does go crazy for it. :X

  7. Wow,
    I never thought about it like this. I always watch youtube videos about dogs manage to find their supplement bag and start eating it, and I always thought it was cute. But now thanks to you I know it can harm the poor creature. Thanks for sharing it.

    1. Thanks Jagulba, we have Erin to thank for calling attention to the dangers of supplement overdose. I guess I’ve always been conscious of it because I used to have a very mischievous cat who jumped on the fridge one day, knocked my vitamin bottle onto the floor, then his brother proceeded to eat them and foam at the mouth. I rushed him to the vet and thankfully he was fine, so that was quite the wake up call. No other cat of mine had ever done that before!!

    2. Oh yes! Supplements are popular with dogs. Glucosamine isn’t the only thing that can harm them. You often find things like ma huang, caffeine, tryptophan, alpha-lipoic acid, selenium, vitamin D, xylitol … the list of dangerous things in supplements is long.

      I’ll be making a post about dangerous supplements soon in my blog, just because this is such a huge issue!

  8. Hello,
    What a great informative post! I just adopted a 6 year old dog so I am sure I will need this kind of information soon.

    Your dog shaming picture is adorable and your page looks great.


    1. Thank you, Erin! I do not often shame my dog, because she’s such a good girl, so it’s a rare occasion that a picture like that is taken! 🙂

  9. This is a great post – and something I’m ashamed I never thought about as a pet owner. As much as I try to keep the treats out of reach…my dog manages to eventually get to them. Do you recommend any dog proof type containers? Also, would these type of treats be harmful to cats as well in larger doses?

    1. Hey there!

      Hindy has the right of it. Put things like this in cupboards way above their heads. I designate the cupboard above the sink as the “dog cupboard”, where all her pills, treats, and other sundries go. Their jaws are so strong, there’s not much that is dog proof. A seamless metal box maybe?

      Glucosamine can be hazardous to cats, too. Typically, they have tiny tummies, so it’s harder for them to eat the amount needed to get to that level, but because the dose related to liver damage is currently unclear, any cat that eats a fistfull of treats could potentially develop the same problem.

      When it comes to supplements, cats tend to be even more sensitive to things than dogs are. Meaning they can get sick from even smaller amounts.

      1. Hi Erin, thanks for including cats in there as well. I’ve told this story a couple of times here already but… I had a bottle of vitamins on top of my fridge, and of course cats love it up there, and we know how much they love to watch things drop off the edge, so one of them threw my vitamin bottle on the floor, it cracked, and his brother ate a few vitamins. He started foaming at the mouth a bit, I rushed him to the vet and he was fine thankfully. These two were particularly “adventurous.”

        1. I have a prevention page up that discusses “cat assassinations”! 😀 They like to “hunt” things right off the counter where dogs and other cats can reach. Counters are never safe!

          1. Cat assassinations – love it! I know they’ll push anything off a counter, shelf, table, fridge. I’m very good about keeping harmful things out of my pets’ way, but definitely dropped the ball with the vitamins. That was many years ago when I was less experienced with animals. Never made that mistake again.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.