Osteoarthritis in dogs is the canine equivalent of rheumatoid arthritis in people. The condition is slowly but continuously progressing and represents a major concern among pet owners. The use of nutritional supplements in canine osteoarthritis treatment results in statistically significant improvements in arthritic dogs. When treating osteoarthritis, reducing joint pain and joint stiffness as primary concerns. In this article, we will review the use of glucosamine for dogs with arthritis-affected joints. We will describe what glucosamine is and why joint supplements containing both glucosamine and chondroitin are better. We will also explain the benefits, side effects, and dosage of glucosamine for dogs.

What is Glucosamine?

Glucosamine is a naturally occurring amino sugar made of two main compounds – amino acid (glutamine) and glucose (sugar). As an amino sugar, glucosamine is a vital molecule of the joint fluid. Its function is lubricating and maintaining healthy cartilage. According to Plumb’s veterinary drug handbook, glucosamine is a “so-called nutraceutical that can be used as an adjunctive treatment for osteoarthritis or other painful conditions in horses, cats, and dogs.” Naturally, it is available in three main forms – glucosamine sulfate, glucosamine hydrochloride, and N-acetyl glucosamine (NAG).

Glucosamine Sulfate

Glucosamine sulfate is the most common glucosamine form used in dog joint supplements. Consequently, the use and properties of this form are most thoroughly researched. The glucosamine sulfate used in joint supplements is usually extracted from shellfish, but it can also be synthetically manufactured in laboratory settings.

Glucosamine Hydrochloride

Glucosamine hydrochloride is popularly known as glucosamine HCL and is more concentrated than glucosamine sulfate. Glucosamine hydrochloride is also derived from shellfish, but it does not contain sulfates. Although more concentrated in terms of joint pain management, glucosamine hydrochloride acts similarly to glucosamine sulfate.

N-acetyl Glucosamine (NAG)

Unlike glucosamine hydrochloride and sulfate, N-acetyl glucosamine is derived from glucose and acts as a hyaluronic acid precursor (responsible for joint fluid synthesis). This glucosamine form is rarely used in dog joint supplements. Instead, it is used for managing certain gastrointestinal issues.

How does Glucosamine Help Dogs with Hip Dysplasia?

Glucosamine for dogs has natural and mild anti-inflammatory effects and can relieve joint pain, joint stiffness, and swelling. As a key ingredient in joint supplements for dogs, glucosamine supports the structural integrity of joint cartilage, acts as a building block for new cartilage cells and renewal of the cartilage matrix. Simply put, glucosamine supplements promote healthy joints in dogs and can be used to treat osteoarthritis. The use of glucosamine in the veterinary medicine field is relatively new, but the results of its use are quite encouraging.

Benefits of Glucosamine

While the clinical benefit of other chondroprotective agents remains questionable, glucosamine for dogs has proven effects, primarily when it comes to reduced joint pain. We will briefly explain three studies proving the benefits of glucosamine supplements for dogs.

Clinical evaluation of a nutraceutical, carprofen, and meloxicam for the treatment of dogs with osteoarthritis

In this randomized, double-blind study from 2003, 71 arthritic dogs were divided into four groups – one receiving joint supplements (glucosamine hydrochloride and chondroitin sulfate), one carprofen, one meloxicam, and one placebo. At the end of the trial, after comparing the pain scores and results, it was shown that dogs receiving glucosamine and chondroitin show joint pain relief similar to those in dogs receiving non-steroid anti-inflammatory drugs (carprofen and meloxicam) while dogs receiving placebo did not show statistically significant improvements.

Randomised double-blind, positive-controlled trial to assess the efficacy of glucosamine/chondroitin sulfate for the treatment of dogs with osteoarthritis.

In this positive controlled trial study from 2007, 35 dogs with hip and elbow osteoarthritis were divided into two groups – the first (control) group was given carprofen and the second oral glucosamine hydrochloride and chondroitin sulfate. The group of dogs receiving glucosamine chondroitin supplements showed statistically significant improvements in pain scores, better joint mobility, and improved weight-bearing.

Systematic review of clinical trials of treatments for osteoarthritis in dogs

This study, published in the AVMA Journal (Am vet med assoc.) from 2007, reviewed 16 canine osteoarthritis clinical trials and concluded that joint supplements for dogs (glucosamine hydrochloride and chondroitin sulfate) support joint health and offer joint pain relief similar to that of popular prescription pain medications.

Possible Side Effects of Glucosamine 

Most nutritional supplements come with relatively benign adverse effect profiles. Luckily, the same concept applies to glucosamine for dogs. These are some side effects associated with glucosamine for dogs:

  • Increased water intake and urination
  • Fatigue
  • Tummy issues (diarrhea or constipation).

Extra caution is required in the following situations:

  • Dogs allergic to shellfish (plant-based glucosamine and chondroitin options are recommended).
  • In diabetic patients (since glucosamine is an amino sugar).
  • Joint supplements containing glucosamine and chondroitin should be avoided in dogs receiving blood thinners.
  • The use of glucosamine and chondroitin needs supervision in dogs with asthma.
  • The effects of glucosamine and chondroitin in pregnant and lactating dogs are not evaluated.

To avoid side effects and adverse reactions, stick to the recommended glucosamine dose based on your dog’s body weight. The best way of preventing tummy issues is to give glucosamine chondroitin joint supplements after meals.

When to Start Giving a Dog Glucosamine

It is a popular misconception that glucosamine supplements are only for the arthritic dog. Joint health supplements should be started as early as possible, preferably before the dog starts showing clinical signs and symptoms of osteoarthritis. Dogs predisposed to joint problems (giant and large dogs) benefit from early supplementation – starting from puppyhood. Giant and large breed dogs can start using joint supplements when 8 weeks old. Here is a shortlist of the pets and situations that could benefit from joint supplements for dogs:

  • Young dogs predisposed to joint problems (giant and large breed dogs)
  • Dogs diagnosed with joint mobility issues
  • Dogs that have had joint surgery
  • Dogs that experienced joint trauma
  • Dogs weighing more than their ideal body weight
  • Senior dogs

Glucosamine for dogs is an excellent joint supplement but supporting your dog’s joint health requires more than just nutritional supplements. There are other conventional and alternative methods that and best results are achieved when they are used together.

Glucosamine Dosage for Dogs

When it comes to glucosamine dosage, there are several factors worth consideration:

  • The dog’s body weight
  • The severity of the dog’s condition and joint pain
  • The treatment phase (loading dose or maintenance dose)

Usually, it is advisable to use a high dose for a couple of weeks (loading phase) and then switch to a lower or maintenance dose. Based on the info provided in “Plumb’s veterinary drug handbook,” it may take between 2 and 6 weeks for the glucosamine supplement to start working and exerting its beneficial effects. Overdosing on dog joint supplements (glucosamine hydrochloride or sulfate) is virtually impossible. However, underdosing (giving less than your dog’s body weight implies) will decrease the efficacy of the dog joint supplements. Always talk to your vet before starting to use joint supplements for dogs.

How to Give a Dog Glucosamine

When it comes to glucosamine joint supplements for dogs, the market offers a plethora of choices. Most dietary supplements for dogs are oral – available as flavored soft chews, pills, liquids, or powders. In addition to using dog joint supplements, you can also use some alternative methods for increasing your dog’s glucosamine intake. For example, some dog food manufacturers add glucosamine to their formulas.

What to Look for in a Glucosamine Supplement

The best glucosamine supplement for your dog is the one that is easy to use and contains other joint-friendly active ingredients like chondroitin sulfate, collagen, hyaluronic acid, methylsulfonylmethane (MSM), omega 3 fatty acids, Green Lipped mussels, and Boswellia serrata. Once you find the best glucosamine for your dog, stick to the brand. The “Plumb’s veterinary drugs” manual accents the importance of using the same brand as different brands might contain different amounts of glucosamine.

Joint Supplements for Dogs – Buyer’s Guide

As pet owners, finding the right joint supplements for dogs can be overwhelming. Here are some of the basic considerations you need to keep in mind.

Glucosamine Form

Dog joint supplements feature either glucosamine sulfate or glucosamine hydrochloride. Although they act similarly, the decision of whether your dog’s joints will benefit more from glucosamine hydrochloride or sulfate needs to be made by your trusted veterinarian.

Various Active Ingredients

Unless instructed otherwise, when it comes to promoting healthy joints, it is better to choose a joint supplement with several active ingredients over a product containing only glucosamine.

Chondroitin Sulfate

Chondroitin sulfate inhibits destructive enzymes from damaging joint cartilage cells. It also provides adequate nourishment to the cartilage matrix and promotes water retention, increasing healthy cartilage elasticity and shock absorption ability. In addition, chondroitin sulfate has mild anti-inflammatory effects. Chondroitin sulfate is hard to source and extract. Plus, as a large molecule, the absorption of chondroitin sulfate is highly variable. Therefore, some joint supplement companies manufacture a low-molecular-weight version that is more easily absorbable. Chondroitin sulfate is available in injectable form, and it can be administered directly into the affected joints. Chondroitin sulfate and glucosamine act synergistically – they boost each other’s effects, promoting healthy cartilage and healthy joints. Therefore, most dog joint supplements feature both glucosamine and chondroitin sulfate in one complex formula called glucosamine chondroitin. In fact, you can rarely find pure chondroitin supplements (the glucosamine and chondroitin combination is much more common).

Amount of Active Ingredients

The type of ingredients matters but so does their amount. If the product does not clearly state the amount of each ingredient, it probably contains too low doses to promote healthy joints. Of course, it goes without saying that you must avoid such joint supplements for dogs.

Joint Supplement Ease of Use

Oral joint supplements for dogs come in various forms – tablets, liquids, and soft chews. Most dog owners find the use of soft chews to be straightforward and practical. Dogs think of the soft chews as treats are not hesitant to eat them. Plus, soft chews are easy to dose (even in large dogs) and can be used on the go.

Our Final Thoughts

Treating osteoarthritis is more complex than adding dietary supplements to your dog’s menu. It requires a multimodal approach and extensive joint health support. Since arthritic dogs experience clinical benefits from joint supplements, such supplements are an important part of modern veterinary medicine. However, not all joint supplements for dogs are equally good. Consult with your trusted vet and ask for help choosing the best glucosamine for your dog’s condition.

Frequently Asked Questions

Is glucosamine helpful for dogs with hip dysplasia?

Yes, glucosamine supplements are helpful for dogs with hip dysplasia. Ideally, look for joint supplements that have glucosamine and chondroitin sulfate in one glucosamine chondroitin formula.

How much glucosamine should I give my dog?

It depends on your dog’s body weight, level of joint pain, the severity of the dog’s condition, and the osteoarthritis treatment phase. Ask your vet which dose is best for your dog.

Can I give my dog too much glucosamine?

Overdosing your dog on glucosamine is virtually impossible. For example, the loading dose is usually twice bigger than the regular dose, and dogs tolerate it really well. However, consult with your vet before starting your dog on a glucosamine supplement.

Can glucosamine and chondroitin be used together?

Yes, glucosamine and chondroitin act best when used together. In fact, most joint health supplements feature both ingredients in one complex known as glucosamine chondroitin.

Can I give my dog human glucosamine chondroitin supplements?

No, dog owners must not share their human glucosamine supplements with their dogs. This is because human joint supplements have an artificial sweetener – xylitol. Xylitol is extremely toxic to dogs. If the product contains only glucosamine, then it is safe. However, the best glucosamine for dogs is the one your vet recommended.

author avatar
Katelyn Son