Cartrophen For Dogs

cartrophen for dogs

Cartrophen is a brand name for the, slightly less catchy, active ingredient: pentosan-polysufate-sodium. Cartrophen for dogs is an anti-arthritic drug is used to treat osteoarthritis. This medication is veterinarian prescribed only, and often given subcutaneously by injection under the skin. Cartrophen injections are usually given to your dog once a week for a month. Although Cartrophen tablets do exist as capsules, they are not as popular due to a lower precision by body weight.

Most arthritic dogs treated with subcutaneous Cartrophen show improvement. This makes this treatment a good tool to combat the chronic pain caused by osteoarthritis. We all know dogs love to run about, even late into life, so anything that inhibits this is something we need to take measures against. Cartrophen injections in dogs may have the ability to mitigate these horrible effects.


There will always be risks no matter what we’re treating our dogs for, but it’s always important to keep in mind what we’re trying to prevent. Cartrophen side effects in dogs are usually very mild, and definitely worth risking to keep away the awful suffering arthritis can induce. Scientific ‘Cartrophen for dogs’ reviews have shown that this treatment usually brings dogs back comfort they would have sorely missed.

Osteoarthritis in Dogs

Osteoarthritis is a condition that causes progressive joint pain, pain that gets worse and worse without intervention, and typically occurs in older dogs. It’s an incredibly complex collection of symptoms, some aspects of which we don’t yet fully understand. It’s also the most common kind of arthritis, and a condition many readers will be all too familiar with.

This ailment starts with the breakdown of cartilage. This spongy material helps to shield both dogs’ and humans’ joints from the stress of impacts. A dog with osteoarthritis finds itself unable to properly maintain this cartilage leading to the aforementioned breakdown. As this layer of defense fails the other cushioning material in their joints, synovial fluid, starts to fail as well and the joint becomes inflamed. This inflammation, along with the lack of adequate cushioning, can cause severe pain on movement that gets gradually worse and worse.

cartrophen for dogs

Cartrophen for dogs with osteoarthritis

As an anti-arthritic agent, Cartrophen for dogs claims to halt and even reverse the effects, reducing pain by remedying its cause. This isn’t said without evidence either, a 1996 study on petosan polysulphate showed its ability to improve dog’s willingness to exercise, and reduce joint pain. So if your pooch has been booked in for a dog arthritis injection, Cartrophen is likely the drug at work.

Osteoarthritis is the only condition for which the manufacturer recommends using Cartrophen for dogs. Vets will therefore make sure that this is the cause of your dog’s joint pain. This is one of the reasons this medicine is prescription only. It would be easy for a dog owner to assume the wrong condition was at fault, and prescribe a useless or potentially dangerous treatment.

Forms of Cartrophen

So, what form will my dog receive Cartrophen in? Do Cartrophen tablets for dogs exist? Cartrophen is a prescription only veterinary drug that usually administered subcutaneously, that is to say by injection. It is available in oral capsule form as well in some countries, although most experts agree this is not the best way to administer this drug. Most of the successful veterinary trials of Cartrophen for dogs have involved injections, not tablet use.

The issue of precision is also worth noting here. The most effective dose of Cartrophen needs to be quite carefully calculated, we’ll go into that a bit later. Capsules are usually 100mg. This could, depending on the weight of your dog, leave you quite far of the mark.

The cost of Cartrophen for dogs in the form of an injection is likely to be more than the capsule. You’ll be paying for your vet’s time as well. It seems worth it though, to ensure the best possible treatment for your beloved pooch.

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Cartrophen injections for dogs

Cartrophen for dogs is injected by your vet in a similar way to vaccinations. The procedure itself is quick and no more unpleasant than your dog’s routine inoculations against diseases.

The pentosan polysulfate containing liquid is measured out precisely by a vet, and administered by them. Due to the nature of this treatment and potential overdoses, not to mention the inherent danger of an inexperienced person performing injections, it’s not something that can be done at home.

This is though, when carried out by a vet, the course of action that seems most recommended by the company themselves. There are great reviews out there from numerous dog owners. But we should always take individual Cartrophen injections for dogs reviews with a pinch of salt, people can be biased or misinformed. The body of evidence is what makes vets confident that Cartrophen will work.

The standard Cartrophen dose for dogs is 3mg per kg of weight. Studies point to slightly less (1mg) and slightly more (5mg) producing less favorable results.

How frequently to give Cartrophen to dogs

A typical course of Cartrophen for dogs will run four weeks, with one injection every week. This is more difficult to get wrong than the more familiar courses of tablets. Rather than remembering to give a pill twice a day, we instead have a weekly vet visit for a month. Cartrophen injections for dogs cost a different amount depending on the country you live in, and sometimes the individual vet.

The positive effects of this treatment have been shown in studies, but they won’t appear straight away. Like most effective treatments this is not a quick fix. Improvement will probably be visible after the second weekly injection, but may take longer.

At each injection your vet should check your dog for symptoms and improvement, and will likely also ask you if you’ve noticed any difference yourself. Vets should, however, always back this up by testing flexibility and activity themselves. Sometimes just thinking your dog is getting the treatment he needs can cause your to bear false witness. After the course is completed the positive effects can last for a year, but it can be shorter. Treating arthritis is about maintenance and pain management, there is no real cure.

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Cartrophen for dogs side effects

Medicine is rarely without side effects and potential risks, Cartrophen is no exception. While taking Cartrophen, dogs can experience a few unintended effects. With Cartrophen injections for dogs side effects are usually mild but still worth noting.

The more common side effects can include vomiting, diarrhea, lethargy, and anorexia. As with most drugs these effects should go away given a little time, but nonetheless are still enough to concern owners.

Due to the potential to upset your pet’s stomach it’s essential to keep him well hydrated while he undergoes a course of Cartrophen for dogs. The potential for lethargy and anorexia does make this medicine a little different from some others in terms of side effects. Once the course is complete your dogs full appetite should return, but if it doesn’t it might be best to talk to your vet.

More serious side effects of Cartrophen in dogs are occasionally reported, like nasal bleeding and blood in the stool. If you notice either of these it’s best to get in touch with your vet straight away. Symptoms like these might be minor, but could indicate internal bleeding. It’s important to point out that these effects are very rare.

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It’s worth mentioning that, if you are giving your dog any other medication, you should make your vet aware. Vets are very cautious about using this drug on animals taking any drugs that effect blood clotting or blood pressure in general. It’s also suggested against for dogs close to the time of surgery.

Should this put me off Cartrophen for dogs?

We don’t think so, no! Side effects are scary, the last thing we want is for medicine to make our dog more unwell. However, it’s worth bearing in mind that osteoarthritis can cause a huge amount of suffering, and it’s in the nature of this kind of condition that treating it incurs risk. Cartrophen in particular is actually especially safe, with side effects appearing relatively rarely.

Cartrophen for dogs - The Information You Need About The Drug Your Dog Is Taking

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Pippa Mattinson is the best selling author of The Happy Puppy Handbook, the Labrador Handbook, Choosing The Perfect Puppy, and Total Recall.

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  1. My Daisy is a 12 yr old bichon/yorkie mix, spayed. When she was a puppy she had a hip operation due to the hip bone growing outside the hip socket. The vet told me that she would most likely have arthritis at some point in her life.

    Two years ago she could not lift her backside off the floor. My vet suggested Cartrophen. She’s been on Cartrophen ever since with no side effects whatsoever. I am sorry for those who have experienced awful side effects.

    I give Daisy her injection at home. It is carefully measured by the vet according to her weight. I did notice that her stool got a bit darker at first, but she didn’t display any other signs. Her stool has been pretty normal ever since, she has a good appetite, runs like the wind, greets me in the morning with a bouncy smile (time for breakfast), in short she behaves like a puppy again.

    Cartrophen saved my Daisy’s life, in my opinion.

  2. My 21 month old Bernese Mountain Dog starting to have problems limping on his paw, he underwent 3d xray’s and was diagnosed with bone fragments in one elbow and cracked bone in the other elbow, he underwent surgery on both elbows, and I was informed that he has the beginning of Ostio on both elbows, he recommended giving him a series of 4 injections every week, then once a month for life, so far this has been working out very well, it has been 3 months now, he is able to go on walks again, and acts like a puppy, no issues with appetite, only after getting the injection (i do it at home) he will have a loose stool and becomes very quiet for the first day, my dog weighs 53kg and receives 1.60 ml

  3. My 13 year old golden retriever was showing signs of arthritis in his front right paw and left hip. Took him to the vet 3 weeks ago. They immediately started him on cartophen injections and pain relief tablets. After the first injection, less than 24 hours later, he was lethargic, wobbly and appeared depressed. I rang the vet the next day to report his symptoms and hey said side effects were rare and he would be fine? Took him back week two for second injection – wish I hadn’t. He declined in the following days, became more lame, distressed, lethargic and panting like he was going to have a heart attack. I again rang the vet and they said he was just hypersensitive and would be fine? I was convinced it was due to the cartophen and pain relief but again they dismissed my concerns. 24 hours later he began to vomit bile, was disoriented, panting like he’d run a marathon and could hardly stand up. I rushed him to the vet the following day who insisted his symptoms were not associated with the cartophen. But He was admitted to hospital, put on a iv to be rehydrated and underwent a gammitt of tests. The results an acute case of pancreatitis – never had it before and nothing had changed in relation to his diet, although the vet insisted it had nothing to do with the cartophen I know my dog and I’m telling you his near death experience was directly related to the cartophen injections. I am not continuing with this hideous treatment that so many vets swear by and will continue managing his arthritis using natural sources such as strict diet, rose hip vital and good old fashioned bone broth. Be very wary of this drug.

    • I found your comment because I’m having very similar concerns with my dog. We are together 80-90% of the time. We have trained together from day 1. I read animal behaviour books as if they are all about to disappear. I haven’t needed to rush to the vet yet though the change occurred within 90 minutes of the initial injection and he has stayed unwell for the entire week and the vet keeps telling me “It’s ok”. I keep seeing him drop more with each injection. I’m not doing the last injection unless they take some serious time to show me it’s ok.

      I haven’t looked at the studies but this article is clearly skewed in the pro. Even how it doesn’t touch on with any depth of the side effects. It scares me when side effects are glossed over and only the optimistic side of a drug is looked at.

      My poor fluffy dude. It would hurt me so much if I found out that he is sick and all I’ve done with these injections is cause him more suffering. I don’t know if I could ever move past that guilt.

      I want to list some clear side effects: Constipation and unusual bowel movements, unusual panting, withdrawn, won’t play with his best buddies, wobbly on feet, majorly depressed, he won’t move for hours and hours, some days no interest or at least less food interest, he looks swollen, almost complete stop to reactivity to other dogs who he’s been reactive to for many years, he looks fearful in his eyes as well as depressed, other dogs who know him and are mates have been avoiding him.

      Yes, to me, in my experience, dogs are treating him like he is a risk to their health.

      To back my experience up that makes me believe it is the injection, 30 minutes before the injection we were having a great stroll, the same stroll I’d have had with him for the past year. Slightly slower with his arthritis but overall he is very attentive to me, taking treats and enjoying a great sniff. He was the same dog that he had been every time he jumped out at the vet before his first injection. That’s all gone now. He just wobbles around the block now. He doesn’t even look interested when sniffing. The times he’d try to pull me along because something told him he needed to get there because it was AMAZING, they are gone.

      This is my best mate who can’t tell me what’s going on. This is scary.

    • So glad to decided to not carry on with the treatment. The best person to decide on what is happening with your dog is you. You know all their traits and what is happening with them. I had a doberman who had a problem with his back legs and the specialist vet could not pin point the problem. I did some research and found a disease only in dobermans called Dancing Doberman Disease. It is a neurological disease. I told the specialist who totally disregarded this. I was given all sorts of drugs which did not help him so I stopped them. I then saw another vet who also researched Dancing Doberman Disease and he said without a doubt it was this. Always listen to yourself. I now listen to the vets but also take into account my own gut feelings.

    • Thanks for sharing your experience! I have a very small 3 lb chihuahua with horrible patellas (varying opinions on surgery). We have utilized every possible alternative with even the holistic vet suggesting these injections. We started this fall with positive results at first. They suggested monthly injections. During the last one she came home and seem to be struggling to breathe and her eyes suddenly look funny. I was thinking she may have had a stroke. Vet is convinced these injections are not the cause, but she was perfectly fine prior to her last shot. She came around, but even after two weeks she is not 100% herself. She seems so tired ! Even her massage therapist has noticed her normal spunk is not there. She has been examined twice where they say she is fine & was given eye drops for her eyes. I am so concerned I am thinking of having blood work completed just to rule everything out. She is suppose to have another injectionsoon, but my gut instinct is to pass on this. She most definitely is having some type of reaction. I am no vet, but know my dog so well.

  4. Our small dog has had her 4th injection 2 weeks ago and since last one she has been unwell, vomiting, irregular bowel habits , is totally withdrawn now spends her time under our bed or in a space under bench when outside totally out of character for her also she is limping in the back end more than before , I definitely won’t be following this treatment up, as she still seems to be deteriorating

  5. Our Cocker Spaniel 15yrs now has been on Cartrophen for 4 yrs. Initial 4 wks of injections then monthly since. Gives no sighns of pain but now very gingerly in sit/laying etc. 3 wks ago went to Vet for grooming and Cartrophen shot, 5 hrs after shot and 2hrs after food extreme vomiting and diarrhea and collapsed. Drip and With much care from family no better. Suspect overdose of Cartrophen, has any one elso had adverse stomach issues.

  6. I started my 8 yr old corgi on cartrophen in July. After a month or so, she was not limping nearly as often, but her stamina was low. Now (early Nov.) she is high energy and back to walking 5+ km with no problem. Other than being lethargic after the first injection, we have seen no side effects. Impressed!
    We do have her on glucocasime too… vet said to continue

  7. I am in Australia. My dog Bernese, 37 kg, she is tired after her 3km walk. She has had three weekly doses now. Before the cartrophen she had a sore paw and sat down on the way home.The first day of the injection she is quiet and withdrawn. The next day she is distressed , does not eat or drink. Hides in the garden, reluctant to move . The third day she moves little, does not drink or eat; walks a few metres. Fourth day some improvement, she drinks a little, comes inside. Walks 100 metres. Pants constantly and displays distress. Sometimes she cries a little when she turns quickly. Day five she walks up and down the street, and is almost back to her normal happy self. She walks one kilometre. This improves the next day.
    It is extremely surprising to read that the symptoms of this drug are mild. This has not been our experience with our usually happy, healthy, active Bernese.

  8. My 15 year old cattle dog has been getting the injections for 18 months. I could see very little if any improvement in her mobility but her breathing had become so laboured I was at the point of weighing up whether or not I should put her down. Stopped having the monthly injections and low and behold her breathing is almost normal again and she can walk more than 10 steps without coughing and gasping. The vet said the coughing etc was due to a heart murmur. Hmmmm! Time will tell!

  9. Oh my god , my dog is 16 yrs old OTHER THAN ARTHITIS SHE WAS FINE and I was recommended Cartrophen , for her because of bad atheists first week was fine then second week I started to c her struggling to walk ,she was vomiting, I told the vet , she said it’s normal, and after all her shot she will be fine , after HER third week , she wasnt good at all , she contioulsy vomit stop eating for 4days drank once in 4 days , in the forth day she couldn’t breath that well ,
    In the middle of the night around 3 AM on sunday june 28th 2020, she WOKE ME UP ,I heard heard she was struggling to breath ,brought her to the emergency, he said she is very I’ll, fieces in stomach , liver ,name it ..all this because of this bad bad drug ,
    I’ve should of listen to my instance not to go the third time for her shot, she didnt want to walk that way , my dog was given me a sign not to go this way , I should of listen to her signs she knew , poor her now she is DEAD😥😥 ALWAYS LISTEN TO THE SIGNS THAT YOUR DOGS SHOWS U , I FEEL SO GUILTY, SHE WAS TALKING TO ME IN HER LANGUAGE ,

  10. I used this drug on three dogs, a routine and two neapolitan mastiffs. My neighbor used it in his lab. All four dogs showed mobility improvements. All four dogs also developed mammary cancer. Cartrophen was the common denominator in each case . Cancer was non existent in each I’d these dogs. This is the only time I have ever seen or heard of breast cancer in a Male dog. I would never use it recommend cartrophen again.

  11. My 9 year old chihuahua has regular Cartrophen injections. I can really see the difference in him. He’s getting maintenance injections alternate months.

  12. I have a 14 year old labrador cross Springer he is stiff on his legs so my vet suggested cartrophen. After his first injection his mobility has worsened and could not get up the stairs when he could usually but with a struggle. That started the first night after the injection. He’s had his 2nd injection and his mobility is awful, he can hardly walk. Why is this? Has this happened to anyone else’s dog?

  13. My Labrador lennon is today having his 4th injection. He hasn’t had any side effects so far and is not limping at all. My vet stated that after these 4 weekly injections he will have 1 every 8 weeks. Also the article states it has to be done by the vet but I do mine at home. Lennon is so scared of the vets that he is a total mess when we go. So vet taught me how to administer the injection, it’s really easy, and every week I go and pick it up. They have it measure out in the syringe ready for me to pick up, in the fridge, and I have an hour to give it to him. All working great so far.

  14. Given the potential risks, would anyone use this on a three pound dog (patella issues & varying vet opinions on whether or not surgery would work)? I am very concerned with giving her anything (she is so small that the slightest reaction could be fatal). She seems to tolerate holistic supplements very well & currently walks etc. The vet is thinking of using this as a preventative measure to help prevent arthritis setting in. Anyone have a very tiny one that has used this before? I would love feedback from other dog owners.

  15. My 16 year old Staffy X jack russell, just finished her 4 injection course and has such a bad appetite. I am having to feed salmon just to get her to eat. The poor thing seems to have suffered every known side effect. However she can walk a lot better.

  16. We have just started our young golden on this treatment. She has just started into her 3rd month of treatment. We noticed a considerable difference by mid treatment in the first month. Second month was great and noticed by the fourth week she was starting to show signs of stiffness. It has been just a few days since her third monthly treatment and WOW what a difference. She is energetic and happy. She’s very eager to play and go outside to get some exercise. She is back to being the puppy she is! I hope this treatment continues to work for her. So far I feel the results are far outweighing the cost…

  17. My dogs was almost lame but after just 1 dose he stopped crying evertime he laid down The stride was back in his step after a few days. Gave him the second dose and for about 12 hours he seems lathargic but then he was like a puppy again not a 12 year old dog. He has not had any other symptems and his appetite has improved. He was nervice and skitish all the time hidding under the dining room table but now is out and about most of the day. Would recommend this treatment from what I have seen so far.

  18. I am also in Canada. I have 2 of my three dogs on cartrophen injections. They started out once a week for 4 weeks and now they are once every 4 weeks. They weigh in at 75 and 100lbs. Their doses are 1ml and 1.25ml. These injections have given my oldest dogs her mobility back. Some days she’s terrorizing the boys like she is a puppy again. I fully believe in them

  19. We have recently started our dog on cartrophen injections. Like the article stated the first round is a series of 4 injections (1 per week). The next round is 1 injection per month or every 4 weeks whichever is the lesser of the two. This monthly series of injections was not mentioned in the above article. Our dog weighs in at 85 lbs and receives 100 mg/ml which is prescribed for dogs 80 to 120 lbs. The above article says 3 mg per kg of weight. In my case this dose should be 116mg. Is my dog being properly dosed? We live in Canada if that makes any difference in prescribed dosages in other countries.