Disclosure: This post contains affiliate links, and if you click on them and purchase a product, we will receive a small commission at no extra cost to you. Goodpetparent.com only shares products that we strongly believe in and feel would be beneficial for our readers.
When I was in veterinary practice, we always got REALLY excited whenever the latest veterinary miracle drug made its debut. What made them “miracle drugs” was that they usually managed to hit the elusive sweet spot between providing much-needed help for patients while simultaneously offering something very cool (and usually uber-convenient) for pet parents.
The thing to keep in mind is that all drugs, even the miracle ones, come with side effects. A veterinarian’s job is to weigh the potential risks of a drug against its potential benefits for each individual patient. Sometimes the benefits outweigh the risks, sometimes they don’t.
The newest round of veterinary miracle drugs, like many of those that have come before them, sound almost too good to be true. And of the medications mentioned in this post, all have undeniable benefits when used in the right circumstances. However, not every drug is right for every patient, so it’s important to recognize when the risk of using these drugs may be greater than the reward.
Here are three of the current miracle drugs on the veterinary market that may pose potential risks for your pet.
Miracle Drug #1: Apoquel
Introduced in 2014, Apoquel works by suppressing the immune system of severely itchy dogs. It promised to “provide onset of relief within 4 hours” and “effectively control itch within 24 hours”, and amazingly, it did just that. For dog parents who had watched their severely allergic best friend scratch themselves literally raw for weeks or months at a time, Apoquel was a dream come true. Additionally, Apoquel was marketed as a much safer alternative to corticosteroids, which can cause serious damage to the body when used long-term.

But here’s the challenge: Apoquel works by blocking substances in the body called kinases (specifically ones called “JAK’s”) and cytokines, which are linked to the sensation of itching. However, these compounds are also necessary for the body’s immune system to function properly. JAK1 works to constantly survey a dog’s body for invading parasites, fungus, bacteria, viruses, and abnormal cells that may become cancerous. JAK2 is vital for the production of red and white blood cells and bone marrow.
Whenever you block these kinases from doing their jobs, the body’s immune system can be severely compromised. Red and white blood cell counts can go down, leading to anemia and a weakened immune system that can make the body more susceptible to infections. And without the ability to locate and destroy abnormal cells, the risk of developing cancer can increase.
Apoquel is primarily marketed for patients whose itching is caused by an allergic reaction called atopy. However, since Apoquel strongly suppresses the body’s immune system, if a dog’s itching is caused by parasitic mites in the skin or a bacterial skin infection, Apoquel can cause the condition to dramatically worsen. Some veterinarians have witnessed an overgrowth of Demodex mites (which live naturally in the skin and are normally held in check by the immune system) in dogs on Apoquel, which can lead to a flare-up of demodectic mange. Others have had to discontinue Apoquel in some of their patients due to the development of a condition called bacterial pyoderma, an infection of the skin that occurs from an overgrowth of bacteria.
Apoquel definitely has its place in veterinary medicine. For dogs with severe itching who only need it for a short period of time, it can provide much-needed relief. However, any time you’re using a drug that suppresses the body’s entire immune system (not just the itch), much care should be taken to consider the long-term effects.
Miracle Drug #2: Convenia
Convenia is a long-acting antibiotic that is administered by injection. It’s FDA-approved for the treatment of skin infections, wounds, and abscesses in dogs and cats, but it’s also commonly used off-label for urinary tract and respiratory infections, and after dental procedures.
One injection of Convenia provides up to 14 days of constant antibiotic therapy, without the need for pet parents to give their pets multiple doses of medications at home. Sounds great, right? For those of us with hard-to-pill cats, this sounds like a downright godsend.
But here’s the catch – after 14 days, Convenia doesn’t just disappear from the body. Unlike traditional antibiotics, which the body quickly metabolizes and clears, Convenia stays in the body for approximately 65 days after being injected.
Why this matters is because if a pet has an allergic or adverse reaction to Convenia, there is absolutely no way to get this drug out of the system. Convenia’s own drug insert states that the following adverse reactions have been reported:
- Vomiting
- Diarrhea
- Seizures
- Facial swelling
- Loss of appetite
- Anemia
- Anaphylaxis (a life-threatening allergic reaction)
- Death
The drug insert also states “Adverse reactions may require prolonged treatment due to the prolonged systemic drug clearance (65 days).” So as opposed to adverse reactions with more traditional antibiotics, where the body is able to clear the drug within hours, adverse reactions with Convenia are much more dangerous.

The greatest appeal of Convenia seems to be the convenience for pet parents. This leads to Convenia being used in cases where there are safer choices available. For hard-to-pill cats, medications can be compounded into a fish-flavored or chicken-flavored liquid by a compounding pharmacy. Pill Pockets, which are made of a soft and flavorful dough-like substance that can be molded around a pill, are another great option for hard-to-medicate dogs and cats.
Like with other veterinary miracle drugs, Convenia has its place. It can be helpful in cases such as for feral cats who have wounds or abscesses and can’t be medicated on a regular basis, or for older people with feisty animals who simply are not able to medicate their pets. But for most pet parents, oral medications – although they can be more time-consuming to administer – are a much safer alternative.
Miracle Drug #3: Oral Flea And Tick Medications
Oral flea and tick medications for dogs first made their debut in 2014. These typically come in soft, tasty chewables that, once swallowed by the dog, begin killing existing fleas and ticks on the skin within hours, then provide continuing protection for up to 12 weeks. Two of the most popular oral flea and tick meds, Bravecto and Nexgard, are available only with a prescription and work by attacking the nervous systems of fleas and ticks that bite a dog who has these drugs circulating in his bloodstream.
First, let me say there are many people (veterinarians included) who swear by these products and consider them to be very safe. However, I have several concerns about their use. First, I personally believe these medications are routinely overprescribed, since despite being marketed as a miracle product that all dogs should be taking on a regular basis, not all dogs need to be on continuous flea and tick medications.
Additionally, Bravecto and Nexgard (and other drugs like them) are systemic, meaning that once they are taken into the body they are present throughout the entire body. And similar to Convenia, they are also long-acting. This presents the same challenges as Convenia when it comes to the possibility of adverse reactions.
According to information found in the CVM’s Adverse Drug Event database, when given orally, Bravecto had reports of over 70 different types of adverse reactions in dogs, including:
- Vomiting
- Lethargy
- Diarrhea
- Loss of appetite/Refusal to eat
- Itching
- Seizures
- Behavioral changes
- Abnormal blood test results
- Trembling
- Fever
- Ataxia (lack of coordination of muscle movements)
- Death
These drugs also require fleas and ticks to have to bite the dog in order to be killed. For dogs with flea allergy dermatitis (an allergic reaction to flea saliva that causes intense itching), this is certainly not an ideal way to remove fleas.

I personally believe there are safer alternatives to oral flea and tick medications. Although topical flea and tick treatments (liquids or sprays that are put directly on a dog’s skin) still contain chemicals that can cause adverse reactions, because they are placed on the skin and not put systemically into the body, they can be quickly washed off if a reaction should occur.
There are also natural flea and tick repellents available for dogs and cats (such as Wondercide and Diatomaceous Earth) that may be perfectly suitable for many pets, especially in cases where an infestation is mild.
Veterinary Miracle Drugs: Know The Facts
There is no doubt that “miracle drugs” have their place; however, they may not be right for everyone. Any time your pet is prescribed medication, don’t be afraid to ask questions, especially when it comes to potential risks.
And remember, you and your veterinarian are partners when it comes to the health of your furry kids. Understanding all the benefits of a medication versus the potential risks will help both you and your vet make the very best decision for your pet.
Have you ever used any of these medications for your pets? If so, what was your experience? Please tell us about it in the comments below!
Our vet recommended the first drug to us for our lab but did not tell us any of the side effects. Glad we declined it and stuck with the low dose steroids for our lab,s itching.
Hi Tracey! Although it’s true that Apoquel has its place in certain cases, it’s definitely not for everyone. If your dog is doing well on low doses of corticosteroids and is being monitored by a veterinarian for any side effects, that may be all that’s needed, especially if the itching is related to seasonal allergies. Just make sure to watch for any changes in your dog’s appearance or behavior that might indicate an adverse effect and let your vet know about it as soon as possible. Thanks for writing! 🙂
This is such great information, I truly appreciate the details and link to the adverse reaction database. I found that one way to help your CAT take his medication is by getting a liquid form if possible and putting drops on their paws… they can’t help but lick it off. You can even try to crush the pills into soft food and stuff the food into their paws, they can’t help but to eat it. It’s extreme but it does work for those difficult cases.
A friend of mine had a very recent experience involving Convenia.
His 4-year old female cat apparently had a urinary tract infection [UTI]; she was otherwise a healthy cat. The cat was taken to a vet [not her regular vet], who as a first-line approach gave her an injection of Convenia.
Within a couple of hours the cat had become “a zombie”—extremely lethargic and not eating or drinking. The cat’s health rapidly deteriorated and two days later she had to be euthanized. The severe reaction was clearly caused by the Convenia injection.
I understand there are many far less risky options to deal with a UTI in a cat, and Convenia appears in any event to be touted primarily for ‘skin infections’. Plus Convenia stays in the body for a long time, as opposed to other non-injectable drugs that the body can get rid of quickly.
Oh, that’s such a sad story…my condolences to your friend on the loss of his cat. 🙁 It shows that these unfortunate situations do happen – and the sad thing is, most people aren’t informed of the risks of Convenia when they are offered the option. Thank you for so much for sharing this – if more people were aware of the risks, no doubt these tragic losses could be completely avoided.
I had 10 cat’s. It wasn’t easy to administer medicine to all. Some were easy and some were a big challange. We crushed the pills, mix it with a few drops of water to make a liquid, draw it up in a siringe, without the needle. Put the siringe in the side of the cat’s mouth and administer bit by bit till it’s all in. Do not give the liquid with force, because the cat can choke.
My cat has had covenia 2 times…had no issues… Both times were for skin issues… She’s 17 and half now.. New vet gave me amoxicilin liquid.. Her water cyst seems infected… Mixed w her food a few times.. But considering my #MasterOverlord is quite the character.. Pills are not an option nor is liquid down her throat.. Unless i want to be murdered for the 100th time. 😁. I just don’t think/i know probably will have to fight to give her the liquid 2 times a day for 8 more days.. and there isnt a compound pharmacy near me… Is there another antibiotic by injection that is safer… to me, this isn’t about “convenient”.. I will do anything for my cat.. But especially her age.. I almost think covenia is the least stressful on her (and me) at this point.. Dont think she’s getting full dose of amoxicilin now as not eating all of food and refusing it… Just wondered if have any ideas/tips/ if im horrible for perhaps wanting to ask vet if covenia is still an option.. Was offered last sat… Had sent vet pics of her cyst, and she swears is an infection.. But they closed at 2pm that day and I couldn’t get there in time (was 1pm) si they left me amoxicilin out front of office under something.. This is an amazing Vet though.. She tries to incorporate holistic approach as much as possible for every animal.. And she’s also well aware of how my cat is.. Her age.. I also worked in a no kill shelter for 2 years.. Im used to giving medicine to cats and dogs.. My cat however.. Is.. Something else.. Lol.. Why i love her… Guess asking.. If its about the only and best option for my cat.. Is covenia that horrible or am i horrible for wanting to ask for it.. Considering i am, because it seems the best healthwise?
My name is Dean, and I lost my baby girl precious last week to convenia. She was having congestion and slightly weezing. Vet lut her on baytril which she took for 2 days.
My wife called the vet on the 3rd of Feb and asked if she could be seen to make sure it wasn’t serious. He told her to come in right away because he had a busy schedule. He did a full exam and told my wife she had clear lungs, heart sounded good and that she was all congested in the head area. He said it was an upper respiratory infection.
He told my wife there’s a shot he could give her as an antibiotic. He never told my wife about the dangers of this drug just said it should work we’ll see if it does or not. That night my little girl died from anaphylaxis shock. 17 hrs later she was dead from this poison. We are devasted my little pug precious was like my daughter. I informed Zoetis and sent in a complaint with the FDA. Don’t know where that’ll get me but that drug took my little girl away from us.
It needs to be removed from the market, and my vet should’ve supplied me with a dose of epinephrine in case of a reaction. I sent my vet an email detailing how he failed to inform us of the dangers and told him how can a dog die from an upper respiratory with no fever, clear lungs, and according to you no hesrt issues.
I have contacted an attorney, inly problem is I didn’t have a necropsy done. First off he didn’t tell us we could’ve, secondly it happened so fast we were just so distraught.
Once vet received my email he called my wife and said he has administered the drug to several animals and never had any issues. He then changed his diagnosis and said he was treating our precious for pneumonia, which os bs, because he never said that when she was there for the shot.
Please don’t let your vet to this to your loved one.
My 10 yr old female cat was killed b Convenia by Pfizer/Zoetis. I didn’t even know she the vet gave her the convenia injection until after she died and I asked for her paperwork from vets office. I took my cat to vet only to get fluids for not eating for a few days. The vet took her in a back room and came back with her and sent me home with Elura and Gabapentin. I paid the front desk people and like an idiot I didn’t look at what I was paying for. I told them to email me a receipt but I didn’t look at it until after she died when I asked for her paperwork. After the vet visit, she was hiding most of the time, I did manage to give her some food and she was now drooling a lot. Days later, her face swelled and she could barley open her eyes. Large clumps of hair were coming out and she had bright red spots on her lower belly. Istopped giving her the Elura and the Gabapentin immediately and took her back to vet and he gave her Depo-Medrol, another long lasting medication from Pfizer/Zoetis. I thought she was having this reaction from the Elura and gabapentin since at this time I did not know the vet gave her Convenia. I had questioned him on why he wanted to give her another drug after she was allergic to the other 2 (which was actually 3 but again I didn’t know at the time) and he said he would do a blood test this time. The first time he did NOT DO ANY tests when he gave her the Convenia Injection. (The Zoetis leaflet says DO A PATCH TEST before administering.) Her skin looked like it was turning to stone (pruritic skin) and her hair was still falling out in clumps with skin attached. Her face was still swelled. And she was getting weaker. I took her back to vet the 3rd time and vet said to give the Depo-Medrol time to work. One week later, she still had the same allergic symptoms, but then her back legs wouldn’t move, then she couldn’t move her front paws, and her skin looked like it was dying. She was struggling to breathe out her mouth. I took her to a 2nd vet and he diagnosed her with a Drug Eruption. She died 2 days later. A list of her symptoms;
Facial Edema, Pulmonary Edema (swelling of the body), Alopecia (hair falling out), Scabs on skin, Diarrhea, Inappetence’s (loss of appetite), Nephrotoxicity (dying of skin) ,Neurotoxicity (limb weakness/loss of vision), Ataxia (loss use of limbs), Anemia (low white blood cells in second test), Drooling, Pruritus (leathery itchy skin), and Death. These allergic reaction symptoms are what my cat had and is on page 5 on Zoetis Convenia leaflet under the heading Foreign Market Experience. After my cats death, I went back to talk to first vet and asked him why he gave her Convenia, he said he thought she might have a dental problem, he also said that Convenia only lasts 14 days. I told him that the Zoetis leaflet says that it lasts 14 days BUT then it also says it STAYS IN THE BODY for 65 days. What the difference between the words LASTS and STAYS, I don’t know. Drug company semantics? I later found out that most vets get drug advice from the sales reps.( Found out from friends and family who have vets in their circles). Fun Fact: If you google how much Zoetis drug sale reps make, its comes up between $60k-$300+K. Just maybe they have an incentive to not give the complete info on what there selling to there clients (vets). I watched the TV show
Dope sick and the sales reps were lying to their clients. I don’t know if that’s if that’s the case with Pfizer/Zoetis who are the biggest drug company in the world.
Several years ago, the use of Convenia to treat a skin infection on my cat’s nose ended up killing him. Note: The veterinarian who administered the injection confirmed this. The day after the injection, my cat could not balance to walk, he was staggering to his water bowl and litter box. Blood work showed that he had hemolytic anemia. FIV and FELV were tested and found negative. More blood work was done, and his levels were far from normal. I had to rush him to the vet, who referred us to the emergency hospital. His breathing was so labored, due to pulmonary edema, they put him in an oxygen chamber, and said that he needed a transfusion. There was no donor cat and they had no blood supplies on hand. He was so ill and suffering, I just requested that he be put to sleep. That was one week after the injection of Convenia. I was not told of any potential side effects. Other cats of mine had been given Convenia previously, and I was never advised of any potential side effects. I now have it written on all my cats medical charts: NO CONVENIA. If you bring up the dangers of Convenia in almost all veterinary medical centers, be prepared to not be believed, and be ridiculed. I actually was in the waiting room at the same facility where my cat was put to sleep, and mentioned it to a person waiting for their pet to be treated. The vet suggested Convenia, and I could not keep quiet. I was polite about mentioning the dangers of the drug. The vet then went on to say that side effects are rare, etc…. I told her if she needed the facts, my cats medical records were on file right there. Please, if you have an option, don’t have your pet injected with Convenia.