Updated November 29, 2020
What if common treatments recommended by your vet are causing deaths in dogs and cats?
‘Does Bravecto Kill Dogs?’ is a popular Facebook group with over 25,000 members dedicated to fighting the use of the popular 3-monthly flea control.
If you visit you’ll see story after story of sicknesses and deaths occurring in dogs who have received Bravecto. Symptoms include:
- Kidney and liver failure
- Skin rashes and sores
- Acute pancreatitis
- Bloody diarrhoea
- Immune-mediated anaemia
What’s the truth? Can this product really be causing these illnesses and deaths? If so it’s a disaster. Bravecto is one of the most commonly used treatments in pet dogs and cats on the planet.
What’s worse, this follows close on the heels of the Beneful and Trifexis controversies.
Are Pet Drugs & Medicines Dangerous?
How is it that people can be so sure a drug is dangerous while vets say the same drug is safe?
Vets will say:
- I know these treatments well
- I recommend them for my own patients
- The drugs have been tested in clinical trials at far above normal doses
- If a drug was dangerous, I would know
- If a drug was dangerous, it would be recalled
Campaigners will say:
- How do you explain all these animals who have got sick after taking the drug?
What about all these illnesses? How do we know if they are being caused by Bravecto?
The first thing is that no one is being malicious; there is no scam or hoax. These illnesses really happened. That’s not in doubt.
- Some of the reports will be true, representing the percentage of adverse reactions we can expect with any treatment.
- Most will be explained by the phrase drummed into me in statistics classes: “Correlation does not imply causation“. What does this mean?
A good example is the long-acting antibiotic injection Convenia. Here’s a very common real world scenario:
- A cat comes in very sick, and clearly in danger. We can’t make a diagnosis from the physical exam, and need to order blood tests.
- It’s not an option to do nothing while we wait for the results. If we can give pills we will, but that’s very difficult and stressful for many sick cats. Therefore we often recommend Convenia.
- Now let’s say the worst happens and the cat gets worse or even dies. Was it the Convenia or the underlying disease? We simply don’t know. Convenia’s use is correlated with the death, but is not necessarily causative.
Here’s one where I was fooled.
Yuki was almost paralysed in the back legs after a routine vaccination. I absolutely believed the vaccine had caused it. Who wouldn’t?
I will always be thankful that her owners took her to a specialist for an accurate diagnosis. She actually slipped a spinal disc in her cat box during transit.
If it wasn’t for the MRI I would have spent the rest of my career thinking vaccines cause paralysis. That’s how hard it is to know what’s safe.
For another view of the correlation-causation problem, have a look at these graphs. Who knew that eating cheese was correlated with being strangled by your bedsheets, or that when Nicholas Cage is in more films there are more swimming pool accidents? It’s true!
Sickness in animals is common enough that there will be many, many times when they are simultaneously on another treatment like Bravecto when they get sick. That’s not in doubt. The big question is: did the Bravecto cause the illness or would it have happened anyway?
Let me put it another way. Let’s say a dog gets sick once a year, so there’s a one in 12 chance a dog will get sick in any month. Therefore one in twelve dogs will get sick within one month of even a yearly treatment like ProHeart or a vaccine. The people whose dogs get sick may associate the sickness with the treatment, and they won’t be aware of the other 92% of dogs happily going along normally.
These events, whether rare or common, will be easily brought together by online groups. It’s the job of the regulators to decide if such events represent the standard rate of illness in the community or occur more commonly when taking the drug.
How Do I Report An Adverse Effect?
One thing that frustrates me is the misunderstanding of the reporting and recall system. Reporting is how we collect these events to look for patterns in the data
That’s how unknown side effects are discovered and known side effects are monitored.
Every suspected adverse effect should be reported to the manufacturer and your country’s veterinary medicine regulator. Here is the link for the APVMA in Australia.
The regulator is then legally bound to make a record of each report.
Here’s where the online campaigns are interesting:
- They encourage every suspected adverse effect to be reported. That’s no bad thing, but if you look at the lists you’ll even see symptoms that are almost certainly from the disease being treated not the drug. For example, skin problems for flea products.
- They then use the same list they had a big part in making to say: “Look how many adverse effects have been reported; we need a recall “.
Here’s what they say on ‘Does Bravecto Kill Dogs’.
“IT DOES NOT NEED TO BE PROVEN TO BE AN ADVERSE REACTION. A coincidence of timing, soon after drug administration is enough to warrant that SUSPICION.”
wwww.facebook.com/doesbravectokilldogs/ Sept 2016
Why Doesn’t The FDA Do A Recall?
I think they learned their lesson with the Proheart debacle. That was the first time one of these online campaigns achieved significant momentum, and they DID recall the drug.
Continued use in Australia and Europe showed Proheart to be safe and it was re-released in 2008 in the USA.
That doesn’t mean reporting problems is a bad thing. We do it all the time and it’s a big part of keeping veterinary drugs safe. There isn’t a drug on the planet that doesn’t have a list of known adverse effects.
The trick is that the raw data needs analysis before it can be used.
- Are adverse effects happening more commonly in treated animals?
- If so, is the extra risk small enough to be justified by the benefits?
Using just raw data or a gut feeling to support a claim is not accurate enough, as I hope you can now see.
Why Are Online Campaigns Successful?
Online campaigns are usually run by very passionate believers. The passion comes through in how they speak about:
- The terrible things that have happened to pets
- The dangers of big pharmaceutical companies
- Conspiracy and denial by vets
They also actively suppress alternative points of view on the pages and sites they manage.
They do all this out of a deep conviction that they are saving lives.
Contrast this with how vets and regulatory bodies need to act. We need to choose our words carefully and stick to the provable facts. It makes us look boring at best, or disinterested or even in denial at worst. We also tend to avoid talking about money even when it’s in our interests to do so.
Here I go then!
- Vets receive no payments from drug companies
- Recommending a deadly product isn’t exactly good business sense
- Most vets are employees & have no financial incentive in the products they sell
- Even when they do the rewards are pitiful: last year my Bravecto sales amounted to 0.25% of turnover.
Why Does It Matter?
Here are three good reasons:
Loss Of Treatments
We battled heartworm in Adelaide throughout the eighties and nineties with only limited success before Proheart arrived. Then within six months of the yearly injection’s release in Adelaide, heartworm disease in dogs went from common to rare.
Vets in the USA are still having problems controlling this disease, and I have to ask if it could all have been very different.
How many dogs died after Proheart was withdrawn who would have been saved? We’ll never know, and the same will happen when any valuable drug gets taken off the market.
I saw a dog recently with heart disease who can’t even go for walks or climb stairs. The shocking thing is that I saw the same dog with the same symptoms a year ago and recommended a good heart treatment at the time.
Little did I know the owner went home, did an internet search and found a site dedicated to the evils of the drug. So out of fear she did nothing and her dog suffered. It’s a terrible irony that the people who care the most for their pets are also often the most vulnerable to misinformation.
If you think pets with fleas don’t suffer, you need to read about the death of my Auntie’s dog Rufus. It’s at the start of our guide to the alternative & natural flea remedies.
Yes, this is also personal. Who among our readers isn’t a perfectionist at work? I don’t know one vet who doesn’t care deeply about the effect they have on their patients or would do deliberate harm. We can at least agree that we’re all on the same side.
Let’s be open about the risks of adverse effects, and let’s also be prepared to change our views based on the evidence. Yes, there will be times when new drugs are found to cause harm, but we have to approach the problem logically or it’s back to the dark ages.
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By Andrew Spanner BVSc(Hons) MVetStud, a vet in Adelaide, Australia. These blogs are from a series regularly posted on email and Twitter. Subscribe via email here to never miss a story!
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