Ultimate Dog

By Luna Lupus - Reading Time: 9 minutes
cytopoint for dogs

Cytopoint For Dogs? Clinical Trial, Veterinary Practice, & Dog Owners’ Experiences

Scratching, licking, inflamed skin – if your dog is suffering from atopic dermatitis, you are battling these symptoms on a daily basis. Caused by allergies, there are several clinical treatment options available for this condition. Immunotherapy (allergy shots), antihistamines, and steroids are among those most commonly prescribed. Unfortunately, these options aren't ideal for many dog owners – sometimes, the side effects alone can be worse than the original symptoms.

Enter Cytopoint: a new type of medication on the market that is non-steroid and non-chemical. A natural antibody that is said to be without side effects. But instead of being an indisputable alternative to other medications, Cytopoint has found itself in hot waters, caught between the opinion of a pharmaceutical company and the first-hand experiences of its users. 

Using Cytopoint for Dog Allergies

The core ingredient in Cytopoint is lokivetmab – an antibody that suppresses itching in dogs. Lokivetmab is a form of protein that binds to another protein called interleukin 31 (IL-31) and blocks it. It is precisely IL-31 that sends a signal for itching, and when lokivetmab blocks that signal, the itching goes away. With Cytopoint, this signal can only be blocked for three to four weeks before a new dose of the medication is needed. It is administered with an injection under the skin and requires a vet appointment. 

The main question with Cytopoint is not whether it's effective in what it's trying to accomplish. Studies have shown that Cytopoint can reduce the itchiness in dogs by more than 50% within the first 28 days. The main question is, what are the side effects? Most drugs come with side effects, and one can hope the companies that manufacture them are as transparent as possible in disclosing them. This is where Cytopoint is different.

The package insert for Cytopoint only states: “Adverse events occurred at a similar frequency between treated and placebo groups in a study of 245 canine patients presented to veterinary hospitals and diagnosed with atopic dermatitis. […] Signs of patient discomfort on administration and adverse events occurred at a similar frequency between treatment groups.” If you read carefully, it's clear that adverse reactions were indeed observed in the clinical trial, but since they also occurred in the placebo group at a similar frequency, they apparently don't need to be disclosed.

Many dog owners who have tried Cytopoint felt blindsided by the side effects they didn't expect. The official information from the pharmaceutical company differs greatly from the users' experiences, and it's reasonable to ask how is that possible? Why were there reactions in the placebo group to begin with? There are several lenses through which we can examine the safety of Cytopoint, but let's start with the infamous clinical trial. 

A Close Examination of the Clinical Trial 

Cytopoint is manufactured by Zoetis, the world's leading producer of pet medication (including Apoquel, a tablet treatment for atopic dermatitis). A clinical study to determine the safety of Cytopoint was funded by Zoetis and carried out by its employees. 245 client-owned dogs with atopic dermatitis participated in the study, of which 162 were given lokivetmab, and 83 were given the placebo.

As already mentioned, there were no significant differences in terms of Cytopoint side effects between the two groups. This means that both groups showed similar, if not identical, side effects. These side effects are outer ear infection, dermatitis, bacterial skin infection, skin rash, vomiting, anorexia, lethargy, itchiness, diarrhea, hair loss, and fleas. The table below shows the frequency of adverse effects in both groups: 

cytopoint side effects
(Image source: Veterinary Dermatology)

Aside from Cytopoint side effects mentioned above, four dogs in the trial had a severe adverse reaction. One developed immune-mediated hemolytic anemia and thrombocytopenia, another was diagnosed with diabetes, and two dogs with pre-existing conditions were diagnosed with lymphoma.

Why did the dogs react to the placebo in the first place? What was in the placebo? The only information we get from the study is that the placebo looked identical to the drug and had the same excipients. Excipients are actually a crucial part of the equation – they are substances without medicinal properties that act as a safe vehicle for the drug. 

As one article states: “[…] in recent years excipients have proved to be anything but inert, not only possessing the ability to react with other ingredients in the formulation, but also to cause adverse and hypersensitivity reactions in patients. These range from a mild rash to a potentially life-threatening reaction.”

It's obvious that adverse reactions did occur in Cytopoint's clinical trial and at a high enough rate that they should have been noted and perhaps even followed up on with more research. Just because the side effects appeared in the placebo group doesn't mean they should get overlooked – if anything, this should have caused greater alarm! Excipients can make up to 90% of the medication, so we have to be aware of what they are and the side effects they can cause. 

Excipients in Cytopoint 

Excipients in Cytopoint (and presumably in the placebo) are histidine, histidine hydrochloride monohydrate, trehalose dihydrate, disodium edetate, methionine, polysorbate 80, and water for injections. Some of these can cause side effects similar to those observed in the Cytopoint clinical trial.

For example: at higher doses, histidine has shown side effects in impaired cognitive function, anorexia, vision impairment, weakness, nausea, drowsiness, and depression. Methionine can cause vomiting, drowsiness, and irritability. Caution is also advised for patients with liver disease. Polysorbate 80 has been connected with side effects of anaphylaxis, rashes, and hypersensitivity. It has also been linked to kidney and liver toxicity, specifically when used as a vehicle for another drug. Clearly, these substances do affect the system, and their effect should have been acknowledged in the original study's conclusions. 

The Safety of Cytopoint in Veterinary Practice

In 2017, a round table report was published about the experience veterinarians had with Cytopoint in their clinical practice. Nineteen veterinarians participated who have given Cytopoint to hundreds of dogs. They have seen a significant improvement in a large percentage (60-70%) of their canine patients' atopic dermatitis after administering Cytopoint. Many of the dogs were itch-free from three to four weeks after the injection. 

Several veterinarians have observed adverse reactions and have even noted that those have been very difficult to report to Zoetis, as the representative they spoke to doubted and minimized the reported effects. The most commonly reported side effects were vomiting, diarrhea, and lethargy. Other noted side effects were anorexia, pain on injection, hair loss, increased itch, rash, and swelling.

These side effects are in alignment with the European Medicines Agency's product information on Cytopoint. Classifying them as rare, they note the following reactions: anaphylaxis, facial swelling, rashes, vomiting, diarrhea, and neurological issues (seizures, ataxia). They also note injection site pain, injection site swelling, hemolytic anemia, and thrombocytopenia, classifying them as very rare. 

Most veterinarians included in the round table have not seen their clients switch to Cytopoint as a sole treatment for their dog's atopic dermatitis. The possible side effects of long-term IL-31 suppression were also discussed, as IL-31 has been found in several essential places in the body, such as mast cells, spleen, bone marrow, ovary, and testes, to only name a few. No conclusions have been made, but there is a concern that blocking IL-31 for a prolonged time might negatively impact other immune functions in the body. 

Dog Owners' Experiences With Cytopoint

We can look at trials and discussions on Cytopoint all day long, but the most potent information comes from people who have seen it work first-hand. If you search the internet for direct experiences dog owners had with this drug, you will find many. Among them, I found two threads that are regularly updated with the most recent encounters. 

The first one is moderated and frequently commented on by a veterinarian. It also provides updates for some of the cases. The second one is a forum, so it's less organized and without a veterinarian weighing in, but you do have people's real-time reports of their experience with this medication. These are the stories that show us how Cytopoint works beyond the clinical environment. 

Weighing the Pros and Cons of Cytopoint for Dogs

Any medication has benefits and risks. When making a decision that impacts the health of our beloved dogs, we have to weigh the pros and cons to determine whether the benefit of a certain treatment far outweighs the possible risks. With Cytopoint, the apparent benefit is the reduced scratching. However, for someone who has been watching their dog suffer the itchy agony for years, this pro alone may just as well outweigh all the possible cons. In this case, it's important to know about the side effects so they can be discussed with your veterinarian and properly prepared for. 

In my view, the biggest con of Cytopoint is the lack of transparency surrounding the side effects. They are neither openly disclosed nor followed up on by more clinical research; they are left up to each individual dog owner to determine and deal with. This is a medication that only works from three to four weeks, so the question is, are dog owners prepared to put their dogs through possible adverse reactions every single month? Another pain point in this area is the pricing of Cytopoint. Roughly estimated, the cost per monthly appointment can be between $80 and $200, depending on the size of your dog. That is without the additional appointments to manage the side effects if they occur. 

Finally, Cytopoint is a relatively new drug. It has only been approved in the US since December 2016 and in the EU since April 2017. The long-term effects of this medication simply aren't known yet, and there is a concern about how sustainable and safe it is when consistently used for months and years. It's important to note that Cytopoint attacks the symptoms, not the cause. It does not cure atopic dermatitis – it only suppresses its physical expression. There are a variety of alternatives to consider, and you can read about them in detail right here.


Cytopoint®.” Zoetis Inc. 

Cytopoint.” European Medicines Agency, 15/09/2021.

Cytopoint Product Information.”  European Medicines Agency.

Cytopoint: Experiences and Questions Roundtable.” American Academy of Veterinary Dermatology, 05/2017. 

Michels, M. Gina. Walsh, F. Kelly. Kryda, A. Kristina. Mahabir, P. Sean. Walters, R. Rodney. Hoevers, D. Jacquelien. Martinon, M. Olivier. “A blinded, randomized, placebo-controlled trial of the safety of lokivetmab (ZTS-00103289), a caninized anti-canine IL-31 monoclonal antibody in client-owned dogs with atopic dermatitis.” Veterinary Dermatology, 19/09/2016. 

Haywood, Alison. Glass, D. Beverly. “Pharmaceutical excipients – where do we begin?” Australian Prescriber, 01/08/2011.

Thalacker-Mercer, E. Anna. Gheller, E. Mary. “Benefits and Adverse Effects of Histidine Supplementation.” The Journal of Nutrition, 10/2020. 

Methionine.” PubChem, 18/09/2021. 

Schwartzberg, S. Lee. Navari, M. Rudolph. “Safety of Polysorbate 80 in the Oncology Setting.” Advances in Therapy, 23/05/2018.

Elizabeth, Hannah. “How Much Does a Cytopoint Injection for Dogs Cost?” Bestie Paws, 31/08/2021. 

Seitz, Sara. “5 Apoquel Alternatives That Are Better For Your Dog.” Ultimate Dog.

Luna Lupus
Luna’s passion for learning about canine psychology and behavior began when she adopted a severely reactive puppy from a local shelter. She is now a big advocate for positive reinforcement and compassionate training. As a writer, she strives to spotlight the topics that fly under the radar and be the voice for all who cannot speak for themselves.
Chirp Superfood Topper With Soil-Based Probiotics

24 thoughts on “Cytopoint For Dogs? Clinical Trial, Veterinary Practice, & Dog Owners’ Experiences”

  1. My dog had a very bad reaction to this drug on two different occasions. I did not put it together until after the second shot. She experiences face swelling, excessive vomiting and bloody diarrhea within days of getting this shot and it lasted for several days and cost me a lot of money. The company paid for me vet bills the second time around. DO NOT EVER USE THIS DRUG

    1. Hi Shaun,

      I’m so sorry your dog had to go through that – I hope she is doing okay now. Thank you so much for sharing your experience with us!



    2. That is too bad. This drug has been a life saver for my girl. She is a whole new dog that enjoys the outdoors, is active now, and her hair had grown back.

  2. Is there a BETTER natural alternative to environmental allergies ?? I really HATE using chemicals or medication that has bad side effects.

  3. My Frenchie has had Cytopoint and his personality has completely changed. He is no longer a happy boy he seems lost. He is a completely different dog and it’s horrible to see. We’ll not be having this again

    1. My Husky was given this last week for itching and has also seemed lost and starring at the walls etc. will not continue giving him this med. ugh!
      His skin as of now is dry and itchy and not sure what is going on, changed his food to salmon-based without chicken, however ??
      Vet visit next week to follow up . So upset!

  4. Veronica Alcántara

    My dog complete two dose’s and even when improved his symptoms and his skin complete healthy had two episodes of neurological events w dilated pupils and tremors w muscle tenderness and contractions.
    We better deal w his skin problem and not seeing like this 🥺

    1. How I wish I would have read your post before I allowed my Golden to be given Cytopoint. Thursday afternoon he was given the treatment and on Monday morning he passed away. Every adverse symptom that has been posted he displayed.

      1. Hi Bill,
        I am so sorry to hear of your loss. I can say my family can feel your exact pain, because we lost our 6 year old healthy dog on 01.18.23…….yes shortly after given his approximately 5th Cytopoint Shot. We saw multiply Vets and no one could tell us what was wrong. All their comments were he is an unusual case. We told all of them that we thought it was from his recently received Cytopoint injection…..NO COMMENTS! It appeared as it just shut down his immune system. After his death, my husband and I starting researching and now find all these people reporting these side effect. Many seem to post and don’t take it any further, and I’m not judging, but I am not going to let this go. I do not want to see another dog die from this possible side effect. I don’t care if they keep selling their drug, but I want to see 100% transparency regardless how rare they feel the event was. I would love to hear from you to get more details. I can be contacted directly at VedoForever2023@gmail.com. Thank you.

  5. My dog was given this shot for a few years and it was causing a lot of cognitive issues . The last time she received the injection she had a severe reaction and the next morning she had a very bad seizure and we took her to the emergency vet and none of the meds helped and we had to put her down the next day. Do not ever get this shot for your pet!

  6. My dog got the shot a couple days later she started vomiting,swaying when walking, lethargic,etc.now 2 weeks later has lost total control of back limbs,falling when trying to get up.Made appt to go to specialist for x-rays to see what is going on.The Vet that administered the shot said she’s old and it’s probably neurological and has nothing to do with shot! Will see.I wish I would have read all this before I did this.I would had never done it.

  7. My dog received cytopoint once a year for three years without difficulty.The fourth shot was the problem.After two days my dog had a seizure.He then had three more seizures over the next three days.He remains very lethargic.He is sleeping up to ten hours a day.Appetite has decreased greatly.His cooordination is off.He barks for no reason.He definitely has changed drastically personality wise.W outdo never give this drug to my dog again.Reported these findings to my vet.Vet stated she reported these to the company but I never heard any more from anyone.

  8. My older Bichan Frise has had two injections of this and both times he has reacted – lethargic and red swollen eyes. I only just now put it together that he’s reacting to the shot. Definitely not getting any more of them.

  9. My six year old Golden had been on Apoquel but it wasn’t really helping with the iching and scratching. My vet suggested we try Cytopoint. This was on a Thursday late afternoon. Monday morning my dog passed away. Every negative symptom that has been posted my dog displayed. Hindsight is always 20/20 but had I taken the time to read these blogs I would not have agreed to Cytopoint and I know I would still have my beloved Golden, Teddy by my side!

  10. My dog was given her third Cytopoint shot on a Monday about three months ago. On Wednesday morning, she had a slight seizure. I say “slight” because she was conscious and looking for help as she didn’t know what was happening to her. I also had a dog with much more serious seizures for me to say “slight”, but no seizure is “slight”! My vet did reach out to a national vet registry and he said no one who responded had seen neurological side effects of Cytopoint. I will die thinking it was the Cytopoint. That was three months ago. Christmas Eve she had another “slight” seizure. I know I am going to be told that it’s epilepsy…well she had none before Cytopoint. Do not give this drug to your dog.

  11. Our precious Cookie was given Cytopoint without our permission the vet said a shot for the itching. Being in the medical field you are thinking steroids normal protocol. When he came back with Cookie he said injection will last 8 to 9 weeks. I said the steroid shot lasts that long? He said I gave him Cytopoint. I said you never asked my permission to give him a new product or even explain to me what it was you were giving him. Our Cookie had a grand maul seizure 35 minutes after administration of the Cytopoint. We took him back to the vet he was given more drugs to counteract the seizure from Cytopoint. We are now 14 days into this very excruciating, frustrating, Sad heart wrenching situation with our dog being lethargic, no appetite, loss of coordination ,staring into no where, neurological problems, cannot urinate had to be catherized to urinate, vision problems, being fed baby food through a syringe, had to recieve fluids for dehydration, hair loss, depression, isolating, back limb problems ,not walking and screaming every time you try to touch him. Has anyone dog come back to being normal? We are praying for a miracle.
    We also have started a case with Zoetis but for now they will only reimburse for Cytopoint. Really???? They know what this drug does. The Vet is making lots of money and he told them our dog did not have this reaction from the Cytopoint.
    We are now are taking our dog to another vet and watching him for a few more days to see if our Cookie comes back to us. This is very sad and heart wrenching our family dog. It has saddened our entire family and we have a big family. Cookie has been a big part of our life for 10 yrs. now we rescued him. For him to go through this is terrible with the good life he has had. Please anyone reading this DO NOT LET THEM GIVE THIS DRUG to your Precious pet. I hope our Cookie story can save many dogs. Thank you.

    1. Hello Michele. My wife wrote the “Vedoforever” comment above (scroll up!). We lost our dog on January 18th due to Cytopoint. We have been in discussions with Zoetis for the past 6 weeks. They sent you a check but did you have to sign a non-disclosure letter that you would not post anything negative via emails, social media, etc???? They are trying to buy off people that complain about their product. We are chasing them down! Please check The European Medicene’s Agency where they have disclosed the fact that Cytopoint can be deadly for dogs. Yet, our own USDA has not. WE filed a formal complaint with Zoetis and are now following up with the USDA. WE ALL need action to remove this product from market or have the vets and Zoetis make it public knowledge to us pet owners of the potential ill effects that their drug has on our dogs.

    2. Victoriasky@yahoo.com

      Hello Michele,

      Hello everyone.

      My dog was given Cytopoint and that evening he had continues grand mal seizures until the morning. It was horrible. He died the following day.
      My doctor assured me that this medication has no side effects.
      I would like to take this to FDA. This medication is not safe for every dog.
      If anyone has any literature or any information about this drug please email me direct: victoriasky@yahoo.com

  12. Mandy Campbell

    Hi there, I have an 8 mth old Maltipoo, he has had skin allergies, and was given Cytopoint, he was given another injection 5 weeks ago, & has had seizures, vomiting, he was at a follow up appointment on Monday past and i told them about seizures& his odd behaviour & they gave him another injection of Cytopoint, which has left him even worse, stares at nothing, looks sad, won’t let me touch him. He is jumping at the least thing,very scared, and wobbly, took him back for a follow-up yesterday 10/5/23, & now he is on gabapentin & given anti sickness injection, he has been left traumatised.

      1. Good morning, my little Vinnie is worse today, he is not eating at all, it’s likely his mouth is sore, & had a couple seizures from last night, I was at the vet on Monday with Vinnie about the issues he was having and they still gave him the injection, Vinnie is normally a happy little man, & he is just a shell at the moment, fingers crossed he gets better but I have saw the affect after last 3 injections, this one is the fourth & is worsening by the day. I told the vet on Tuesday as I have to take him in, she said gabapentin would chill him as he was like a crazy dog, & now they want to do a liver test to see if the toxins are the cause,this Monday which is going to be horrible for him. Now they’re saying he has diabetes, epilepsy, I am lost with this,

  13. I’m glad to hear that there is a clinical trial underway to determine the safety of Cytopoint for dogs. I always worry about potential side effects when it comes to medications my dog takes, so this information is reassuring. I hope the

  14. This medication helped my dogs itching but the next time but she was then diagnosed with diabetes which i wholeheartedly believe came from this medication! Never again.

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