844-436-7691
Recall check: in August 2026 American Regent recalled two lots of Adequan Canine after glass fibres were found in retained vials: lot 3369 (expires 10/31/2026) and lot 25011 (expires 12/31/2027). No injuries had been reported. If you inject at home, check the lot number on your vial and call your vet or pharmacy before using it. Call your vet the same day if your dog has a swollen, hot or painful injection site, unusual bruising or bleeding (nose, gums, stool or urine), vomiting, or is suddenly weak or lethargic.
The short answer: Adequan Canine (polysulfated glycosaminoglycan, PSGAG) is an FDA-approved injection for arthritis in dogs. The label dose is 2 mg/lb (1 mL per 50 lb) into the muscle twice a week for up to 4 weeks, a maximum of 8 injections. The monthly "maintenance" shots and under-the-skin injections many dogs get are common, but they are off-label choices your vet makes. It works better than placebo in the label trial of 51 dogs, but the "rebuilds cartilage" claim comes mostly from lab studies, and the largest placebo-controlled trial in dogs with hip dysplasia (84 dogs) found no statistically significant difference between Adequan and saline. Side effects are usually mild; because it is a heparin-like drug, it should not be used in dogs with bleeding disorders.
By Marc Brannigan and Natalie Mondine, co-founders of HempMy Pet · Published November 7, 2026 · Last reviewed November 7, 2026. We have grown and bottled full-spectrum hemp for pets on our own Colorado farm since 2016. We are not veterinarians — everything below comes from the published veterinary studies, consensus guidelines and drug labels listed at the end.
What Adequan Is
Adequan Canine is made by American Regent. Its active ingredient, PSGAG, is extracted from cow tracheal cartilage and is mainly chondroitin sulfate with extra sulfate groups added. It comes as a clear liquid, 100 mg/mL in 5 mL multi-dose vials, two vials to a box, and needs a prescription.
It is approved "for the control of signs associated with non-infectious degenerative and/or traumatic arthritis of canine synovial joints": osteoarthritis, including arthritis after an injury. The label calls it a "disease modifying osteoarthritis drug" and says plainly that its exact mechanism in dog joints is not known. In the lab, PSGAG blocks enzymes that break down cartilage, reduces a prostaglandin linked to cartilage loss, and boosts production of joint fluid components.
It is not a steroid and not an NSAID. It is a chondroprotective drug, which is why it can be given alongside an NSAID such as carprofen.
Free download · from a Colorado hemp farm
Free: The Dog Owner’s Guide to CBD & Hemp
34 pages. The dog studies (including the one that found nothing), dosing by weight, and a 14-day tracker.
Instant download, plus 25% off your first bottle.
Get the free dog guide →Written by Marc Brannigan and Natalie Mondine, co-founders of HempMy Pet.
Adequan Dose for Dogs
| Dog weight | Dose (2 mg/lb) | Volume per injection | 8-injection course | 5 mL vials needed |
|---|---|---|---|---|
| 10 lb | 20 mg | 0.2 mL | 1.6 mL | 1 |
| 20 lb | 40 mg | 0.4 mL | 3.2 mL | 1 |
| 30 lb | 60 mg | 0.6 mL | 4.8 mL | 1 |
| 50 lb | 100 mg | 1.0 mL | 8.0 mL | 2 |
| 75 lb | 150 mg | 1.5 mL | 12.0 mL | 3 |
| 100 lb | 200 mg | 2.0 mL | 16.0 mL | 4 |
From the label: 2 mg/lb (0.02 mL/lb) intramuscularly, twice weekly for up to 4 weeks. Each vial can be punctured at most 10 times and must be used within 28 days of the first puncture, so small dogs throw some away. For illustration only: your vet sets the dose.
- Route: the label says intramuscular only. Many vets have owners give it under the skin (subcutaneously) at home; that is off-label (see the safety data below).
- Do not mix it with other drugs in the same syringe, and use a new sterile needle every time, wiping the stopper first.
- Storage: room temperature, 68–77°F. Avoid long exposure above 104°F, such as a hot car.
- Missed dose: give it when you remember and carry on with the schedule; never double up.
The Label Schedule vs What Many Dogs Actually Get
The FDA-approved course is short: 8 injections over 4 weeks, and the label says "do not exceed the recommended dose or therapeutic regimen." In practice, many vets follow the loading course with one injection every 2 to 4 weeks for months or years, or repeat a loading course when signs come back. That is a legitimate clinical decision, but it means long-term use rests on clinical experience rather than the approval studies.
How long can a dog stay on Adequan? There is no labelled limit on repeating courses and no published long-term safety trial. The best real-world data is the owner survey below, where dogs had been on it for months to years. Bloodwork once or twice a year is reasonable, especially in older dogs or dogs with kidney or liver problems, which the label flags for caution.
How Fast Does Adequan Work?
From the label, injected PSGAG reaches its peak blood level within 20 to 40 minutes in rabbits and spreads into joint fluid and cartilage, and dog studies show a similar pattern. That is how fast the drug arrives, not how fast your dog improves. In the label trial, the measured improvement came at the end of the 4-week, 8-injection course. Most vets judge it over that loading period; if there is no change by the end, it is worth asking whether to continue.
Does Adequan Work? What the Dog Trials Show
- The label field trial (51 dogs): dogs with confirmed arthritis in hips, stifles, shoulders, hocks or elbows were randomised to Adequan or saline, twice weekly for 4 weeks, with vets blinded. Adequan dogs did significantly better on range of motion and total orthopaedic score.
- Hip dysplasia (84 dogs, 1994): a double-blind trial compared placebo with three doses of PSGAG (2.2, 4.4 and 8.8 mg/kg). The 4.4 mg/kg group improved most and placebo least, but the differences were not statistically significant. No drug-related side effects were seen (de Haan 1994).
- 16 dogs with osteoarthritis (2007): lameness improved in 12 of 16 after 8 injections, alongside a drop in a blood marker of cartilage breakdown. Hind-limb lameness improved; forelimb lameness mostly did not. There was no placebo group (Fujiki 2007).
- Evidence review (2007): a systematic review of dog osteoarthritis trials gave PSGAG a "moderate" level of confidence, the same tier as carprofen, below meloxicam's "high" (Aragon 2007).
Where "rebuilds cartilage" comes from
The cartilage-protection evidence is real but mostly experimental. In dogs whose cruciate ligament was cut surgically to cause arthritis, PSGAG reduced cartilage-damaging enzymes and microscopic cartilage damage compared with saline (Altman 1989). And in pups from hip-dysplasia-prone research litters, twice-weekly injections from 6 weeks to 8 months of age prevented hip subluxation:
That puppy result is striking, but it is 16 dogs, a dose higher than the label's, seven months of injections, and it has not been repeated in pet dogs. So the honest summary is: Adequan improves signs in dogs with arthritis, it protects cartilage in experimental models, and whether it changes the long-term course of arthritis in pet dogs has not been shown.
Adequan Side Effects in Dogs
| Side effect | How common | What to do |
|---|---|---|
| Pain or swelling at the injection site | The most common; 1 incident in the label trial | Call your vet if it is hot, growing or still painful after a day |
| Diarrhea, vomiting, poor appetite | Uncommon; listed in trial and post-approval reports | Call your vet if it lasts more than a day |
| Lethargy, weakness ("depression") | Listed in post-approval reports | Call your vet |
| Bruising, nosebleeds, blood in stool or urine | Rare; PSGAG is heparin-like and can affect clotting | Stop and call your vet the same day |
Source: Adequan Canine FDA label: in the field trial, possible reactions followed 2.1% of injections (injection-site pain, diarrhea in 2 dogs, abnormal bleeding in 1), all mild. Post-approval reports, in order of frequency: vomiting, anorexia, depression/lethargy, diarrhea; some deaths reported.
Under-the-skin, long-term use: a rehab clinic surveyed owners giving PSGAG subcutaneously at home. Of 69 dogs, 13 (18.8%) had an adverse event, mostly stomach upset, loose stool, injection pain or fear of the needle, and most kept going. One dog had persistent stomach upset and one developed low platelets with bruising, which resolved after stopping (Varcoe 2021).
Can Adequan cause weakness? Lethargy is on the label's post-approval list. It is uncommon, but a dog that is suddenly weak after an injection should be checked, especially for bruising or pale gums.
At high doses: in the label's 13-week safety study, beagles were injected twice weekly at 1, 3 and 10 times the dose. One dog at 10 times the dose developed a large hematoma at the injection site and was euthanised. At 10 times, clotting time rose, platelets fell and liver values rose; at 3 and 10 times, foamy cells appeared in the liver and kidneys; muscle inflammation at the injection site was seen in every group and increased with dose.
Who Should Not Get Adequan
- Dogs with a known or suspected bleeding disorder, such as von Willebrand disease, because PSGAG is a heparin-like drug. Tell your vet about anything that affects clotting, including rat-bait exposure.
- Dogs allergic to PSGAG.
- With caution: dogs with kidney or liver disease. Safety in breeding, pregnant or nursing dogs has not been studied.
- Cats: Adequan Canine is not approved for cats; any feline use is your vet's off-label decision.
Adequan vs Librela, NSAIDs and Supplements
| Option | What it does | How it compares with Adequan |
|---|---|---|
| Librela (bedinvetmab) | Monthly antibody that blocks nerve growth factor, a pain signal | Targets pain, not cartilage; often given alongside Adequan |
| NSAIDs: carprofen, meloxicam, Previcox, Deramaxx | Daily pain and inflammation control | Faster, stronger pain relief with more stomach, kidney and liver risk; combinable with Adequan |
| Galliprant | Blocks one prostaglandin receptor | Pain control; compatible with Adequan |
| Oral joint supplements | Glucosamine, chondroitin, omega-3s and others | Not drugs, not FDA-approved; Adequan is the injectable, prescription option |
A 2026 survey of 373 US vets found Adequan among the three most-prescribed non-NSAID arthritis drugs, with gabapentin and Librela (Bird 2026).
Which is better, Librela or Adequan? They do different jobs. Librela is a pain reliever with strong placebo-controlled trial data; Adequan is aimed at the joint itself, with weaker trial data. Many dogs get both, plus weight control and exercise.
Is Adequan Worth It?
It is a reasonable choice for many dogs: it has a clean side-effect record at label doses, no daily pills, and no NSAID-type gut risk. It is most worth trying early in arthritis, as part of a plan rather than on its own, with a clear check at the end of the 4-week loading course. It is less likely to be worth it for a dog with severe end-stage arthritis whose main problem is pain, where pain relief comes first. Cost depends on your dog's size, because the dose is by weight: a 50 lb dog needs 8 mL for the loading course, which is two vials. Ask your vet whether home injections are an option.
Where Hemp Fits
We make hemp oil, so here is the honest version. There is no published study of CBD with Adequan, and no known interaction between them. Hemp is not a substitute for a prescribed arthritis plan, but it can sit alongside one:
- In our own 90-day study overseen by veterinary pain specialist Dr. Robin Downing, dogs with joint discomfort stayed on their existing medications while our oil was added, and every medication change was made by the supervising vet.
- CBD can raise liver values (mostly ALP), so tell your vet and keep up with bloodwork. The figures are in hemp side effects in dogs; how it interacts with other drugs is in our hemp and dog medications guide.
Full-spectrum extract in cold-pressed hemp seed oil, grown and bottled on our own Colorado farm: the oil used in our 90-day joint study, where dogs stayed on their existing medications. Not a replacement for Adequan or your vet's plan. Third-party tested every batch. $99
Shop 1,000mg Hemp Seed Oil → See the StudyQuestions to Ask Your Vet
- Is this the label 8-injection course, or a maintenance plan, and for how long?
- Into the muscle or under the skin, and can I give it at home?
- What volume is my dog's dose, and how many vials will we need?
- Does my dog need bloodwork or a clotting check first?
- How will we judge whether it worked at the end of the loading course?
Frequently Asked Questions
What are the side effects of Adequan in dogs?
Usually mild and uncommon. In the label trial, possible reactions followed 2.1% of injections: brief injection-site pain, diarrhea and one case of abnormal bleeding. Post-approval reports list vomiting, poor appetite, lethargy and diarrhea, with rare deaths. Because it is heparin-like, bruising or bleeding means stop and call your vet.
How long can a dog stay on Adequan?
The FDA label covers 8 injections over 4 weeks, but many vets continue with an injection every 2 to 4 weeks for months or years. That long-term use is off-label and has no published long-term safety trial; an owner survey of long-term use found mostly mild side effects. Regular bloodwork is sensible.
How successful is Adequan for dogs?
In the 51-dog label trial, Adequan improved range of motion and orthopaedic scores compared with saline. In an 84-dog hip dysplasia trial, dogs on Adequan improved more than placebo dogs, but the difference was not statistically significant. A systematic review rated the evidence as moderate, similar to carprofen.
Which is better, Librela or Adequan for dogs?
They do different jobs. Librela is a monthly antibody that blocks a pain signal and has strong placebo-controlled evidence for pain relief. Adequan is aimed at slowing cartilage breakdown, with weaker trial data. Many vets use both together, alongside weight control and exercise.
What is the Adequan dose for dogs?
The label dose is 2 mg per pound (0.02 mL per pound, or 1 mL per 50 pounds) by intramuscular injection, twice a week for up to 4 weeks, a maximum of 8 injections. Your vet may then set an off-label maintenance schedule.
How fast does Adequan work?
The drug reaches the joints within hours of an injection, but improvement takes longer. In the label trial, the measured benefit was at the end of the 4-week, 8-injection course. Judge it with your vet after the loading course rather than after one or two shots.
Can Adequan be given under the skin?
The label says intramuscular only, but many vets prescribe subcutaneous injections at home. In a survey of 69 dogs on long-term subcutaneous PSGAG, 18.8% had an adverse event, mostly mild, and one had low platelets that resolved after stopping. Only use the route your vet prescribes.
Why was Adequan recalled?
In August 2026, American Regent recalled two lots of Adequan Canine, lot 3369 and lot 25011, plus two equine lots, after glass fibres were found in retained vials. No injuries had been reported. Check the lot number on your vial and ask your vet or pharmacy before using it.
Is Adequan a steroid?
No. Adequan is polysulfated glycosaminoglycan, a chondroprotective drug made from cartilage. It is not a steroid or an NSAID, which is why vets often give it alongside an NSAID or Librela.
Is Adequan safe for dogs with kidney or liver disease?
The label says to use it with caution in dogs with kidney or liver impairment, and not to use it in dogs with bleeding disorders. At 3 to 10 times the dose, the label safety study found changes in liver and kidney cells. Ask your vet about bloodwork before starting.
The Short Version
Adequan is an FDA-approved arthritis injection with a short label course: 2 mg/lb into the muscle twice a week for 4 weeks, 8 injections maximum. Monthly maintenance and under-the-skin dosing are common off-label choices. It beat saline in the label trial, but the largest hip dysplasia trial found no significant difference, and the cartilage-rebuilding evidence is mostly experimental. Side effects are usually mild; avoid it in dogs with bleeding disorders, and check your vial against the August 2026 recall lots.
Full-spectrum hemp from our own Colorado farm: alongside your vet's plan, not instead of it
250mg Hemp Seed Oil Dogs under 25 lb $49 1,000mg Hemp Seed Oil Dogs 25 lb and up · the trial oil $99 
5,000mg Large Dog & Equine Oil Giant breeds · pump bottle $199
Grown on our own Colorado farm, third-party tested every batch, no xylitol, nothing artificial, 30-day returns. See the lab results · Serving by weight →
Hemp for Hip & Joint Mobility → See Our Clinical Trial
Librela · Carprofen · Meloxicam · Previcox · Deramaxx · Galliprant · Arthritis in Dogs · Adequan for Horses
Marc co-founded HempMy Pet in 2016 with his business partner Natalie Mondine, the company's COO. HempMy Pet breeds its own hemp genetics, grows them on its own Colorado farm, and formulates every batch in-house under human-grade standards — seed to sale, nothing sourced overseas. Every batch is third-party tested and the certificates of analysis are published. More about us.
HempMy Pet ran its own 90-day study of 37 dogs with chronic joint discomfort. Of the 32 that completed it, 30 (93%) showed a benefit, and 94% of owners reported their dog's quality of life had improved. It was overseen by Dr. Robin Downing, DVM, MS of the Downing Center for Animal Pain Management, with Lori Kogan, Ph.D. and Peter W. Hellyer, DVM of Colorado State University's College of Veterinary Medicine & Biomedical Sciences, and published in the Journal of the American Holistic Veterinary Medical Association. Read the methodology.
Why Dr. Downing: in 2005 she became only the third veterinarian in the world credentialed as a Diplomate of the American Academy of Pain Management. She founded the International Veterinary Academy of Pain Management, is a Diplomate of the ACVSMR, a Certified Veterinary Pain Practitioner and a Certified Canine Rehabilitation Practitioner, and was the AVMA's 2020 Bustad Companion Animal Veterinarian of the Year. Read the published paper (PDF).
This article is general information for dog owners, not veterinary advice. It is reviewed and updated as new peer-reviewed evidence is published, and where the evidence is thin or negative we say so.
How We Sourced This Article
Every claim above traces to one of these.
- US Food and Drug Administration / American Regent. Adequan Canine (polysulfated glycosaminoglycan) label, NADA 141-038, rev. 9/2021: indication, dose and 8-injection limit, vial rules, pharmacology, 51-dog field trial, 13-week safety study, adverse reactions, contraindications.
- Recall. Veterinary Practice News, Adequan injections recalled over potential glass fibers (2026): lots 3369 and 25011 (canine), 24416 and 25265P (equine).
- de Haan JJ, Goring RL, Beale BS. Evaluation of polysulfated glycosaminoglycan for the treatment of hip dysplasia in dogs. Vet Surg. 1994;23:177–181. PubMed.
- Lust G, Williams AJ, Burton-Wurster N, et al. Effects of intramuscular administration of glycosaminoglycan polysulfates on signs of incipient hip dysplasia in growing pups. Am J Vet Res. 1992;53:1836–1843. PubMed.
- Varcoe G, Tomlinson J, Manfredi J. Owner perceptions of long-term systemic use of subcutaneous administration of polysulfated glycosaminoglycan. J Am Anim Hosp Assoc. 2021. PubMed.
- Aragon CL, Hofmeister EH, Budsberg SC. Systematic review of clinical trials of treatments for osteoarthritis in dogs. J Am Vet Med Assoc. 2007;230:514–521. PubMed.
- Fujiki M, Shineha J, Yamanokuchi K, Misumi K. Effects of treatment with polysulfated glycosaminoglycan on serum COMP, CRP, MMP-2 and -9 and lameness in dogs with osteoarthritis. Am J Vet Res. 2007;68:827–833. PubMed.
- Altman RD, Dean DD, Muniz OE, Howell DS. Therapeutic treatment of canine osteoarthritis with glycosaminoglycan polysulfuric acid ester. Arthritis Rheum. 1989;32:1300–1307. PubMed.
- Bird E, Miscioscia E, Montalbano C, et al. Variations in the management of canine osteoarthritis: a cross-sectional survey of veterinary practices. Front Vet Sci. 2026;13:1814641. PubMed.
- Review. White GW. Polysulfated glycosaminoglycan as a treatment for osteoarthritis in veterinary medicine. Open Vet J. 2025;15:4007–4023. PubMed. Also PetMD, Adequan Canine for Dogs.
- Kogan L, Hellyer P, Downing R. The Use of Cannabidiol-Rich Hemp Oil Extract to Treat Canine Osteoarthritis-Related Pain: A Pilot Study. J Am Holist Vet Med Assoc. 2020;58:35–45. Our disclosure: HempMy Pet supplied the hemp extract and reimbursed clinic costs; we had no involvement in any other study cited here.
Spot something that conflicts with your veterinarian's advice? Email support@hempmypet.com and we will correct it.
These statements have not been evaluated by the Food and Drug Administration. Our products are not intended to diagnose, treat, cure, or prevent any disease. This article is general information, not veterinary advice. Never start, stop or change your dog's medication without your veterinarian.
