This post is somewhat off-topic. I wrote it several months ago, after a very stressful year with an adopted German Shepherd who had been diagnosed with fear aggression.
When I write about animal research, I usually focus on its lack of transferability to human health and diseases. The following is a story about medicines for humans that are used on dogs – without much evidence that they are safe and effective.
So here is the story:
Ted came to me with a collar, a leash, mud-caked fur and an attitude. An attitude that shouted: ”I do exactly as I please. And you can’t stop me”. I wasn’t intimidated, because I had lived with German Shepherds before. Ted was possibly angry about being torn away from his familiar environment. How could he know that his new life would turn out to be so much more interesting than being locked all day long in a concrete backyard.
Ted had an assortment of what we humans consider to be “behavioural problems”. The most challenging of these were fierce aggression towards other dogs and his mouthing – he bit me regularly, not severely enough so that I needed medical treatment, but he drew blood. We both needed to learn how we could live together in peace and enjoy each other’s company.
When group obedience training exacerbated Ted’s aggression, I consulted a veterinarian with specialist training in animal behaviour. She suggested we do one-on-one work with a dog trainer, in combination with anti-anxiety drugs for Ted.
The first suggestion made sense. But anti-anxiety drugs for a dog?
Human psychiatric drugs are now routinely prescribed for animals in veterinary clinics around the country. Dogs and cats are the most common animals to be drugged to treat problematic behaviours such as separation anxiety, obsessive-compulsive disorder, aggression and noise phobia.
Animal models are not predictive of human health and we can’t rely on animal testing to predict drug behaviour in people. Surely, this must also be true the other way around: if a drug is safe and effective in humans, we can’t assume this to be true for a different species, such as dogs.
Yet there is very little research to show that drugs like clonidine, fluoxetine (better known as Prozac), trazodone, clomipramine and benzodiazepine are effective and safe in dogs. There are not enough substantive studies available in peer-reviewed veterinary journals for a systematic review or meta-analysis.
A small number of these drugs are registered in Australia for use in dogs; others are used off-label. Off-label use is the practice of prescribing pharmaceuticals for an unapproved use or in an unapproved age group, unapproved dose or unapproved form of administration. Veterinarians are permitted to exercise professional judgement in the off-label use or supply of most drugs.
The most commonly used registered medications to treat canine anxiety include clomipramine and fluoxetine. These are available under the brand names Clomicalm and Reconcile. Many anti-anxiety medications given to animals are the same as those prescribed for humans. Doses, side effects and applications for animals have been extrapolated from human use.
Why are anti-anxiety drugs needed?
Well-adjusted dogs communicate using their voice and body language. Other dogs, and many humans, usually understand this language. Dogs that have not been adequately socialised when young and traumatised dogs may not have learned or lost the capacity to interpret other dogs’ signals correctly. Their capacity to communicate with other dogs and people may be severely impaired. Humans with adopted dogs may not know which past events have led to problem behaviour.
These drugs are prescribed for a range of behaviours that express the dog’s distress and upset the canine-human relationship: nervousness, hyperactivity, scratching, chewing, digging, excess barking or howling, salivation, abnormal urine marking, trembling or shivering and destructive or aggressive behaviour. Usually, the underlying problem is anxiety. While humans can go to a psychologist or psychiatrist and talk through their problems, this is not possible for our furry friends. What action a dog takes in response to fear and distress can vary widely. My friend Ted chose aggression.
Anti-anxiety drugs are mostly prescribed together with a plan for behaviour training. On their own, they are rarely effective. Some vets specialise in the field of animal behaviour and are well placed to assess a dog’s behaviour problems and provide a comprehensive behaviour modification plan.
How common are behavioural problems in dogs?
A representative from the Australian Veterinary Association was not aware of the extent of use of canine anti-anxiety drugs in Australia. He estimated that up to 20% of pets in his own clinic may have behaviour problems.
In the UK, a study involving 1,300 dog owners found that 80% of dogs exhibit some sort of behavioural problem. Thirty per cent were found to have “fears” or “phobias”, while 22.5% were described as having “obsessive compulsive disorders” — such as excessive paw-licking or tail-chasing — and 12% exhibited “separation-related problems” when parted from their owner.
Meta-analyses of antidepressant medications (including fluoxetine) in humans have found only modest benefits over placebo treatment. When unpublished trial data are included, the benefits compared to placebo are inconsequential.
The side effects in dogs include, for example, vomiting, diarrhoea, decreased appetite and weight loss, and lethargy. Seizures are a less common but more severe side effect. Further, it may take weeks or even months for the full behavioural effects of some drugs to be observed.
Some humans turn violent or suicidal when taking antidepressants. We don’t know whether the drugs can have similar effects on dogs.
Anecdotal evidence from veterinarians and dog owners suggests that the drugs seem to work for some animals. Finding the drug that works can prevent abandonment and euthanasia. When used with training, even if the drug does not work, the placebo effect might be experienced by the dog’s human: “All that effort and money MUST have resulted in improvement!” However, reliance on medication alone could mean the root causes of a pet’s problems are not addressed and are likely to resurface, in particular when the drug is withdrawn.
Medicalising problem behaviours can remove feelings of guilt on the part of the humans who are responsible for the animals. In humans, the use of anti-anxiety medications has increased considerably over the past decade. They are a popular choice because they work – if they do work – quickly and involve less effort than psychotherapy. For humans and dogs, a pill is preferable in our culture to the hard work of psychotherapy or dog training over a period of months or even years.
Also, these drugs mean good business for the pharmaceutical industry and veterinary clinics. While humans obtain anti-anxiety drugs from a pharmacy, veterinary clinics dispense the drugs directly.
However, Dr Andrew Knight, Veterinary Specialist in Welfare Science, Ethics and Law, believes that the problem “is not unscrupulous vets or drug companies out to make a fast buck. Rather, it is irresponsible breeders who skimp on crucial socialisation and preventative healthcare, combined with neglect of the basics by too many owners”.
The obvious alternative to drugs is behavioural training. But teaching dogs to let go of old behaviours and adopt new, more appropriate ones is a lengthy task. It requires much time, patience, consistency and money if undertaken under the guidance of animal behaviourists and professional dog trainers. This means many people can’t or do not want to commit to such training.
Initially, I chose behaviour training without drugs for Ted. We had weekly sessions with a dog trainer and daily reinforcement of positive behaviours yielded some progress. Ted started learning more appropriate behaviours, such as walking on a loose leash. I gained hope during summer that we were on the right track and Ted’s problem behaviours would eventually fade away. While I love the heat, Ted didn’t. Hot weather energises me, but it made Ted lethargic.
He calmed down. His nipping decreased to about once a fortnight. We continued work with the dog trainer and Ted made baby steps in the right direction. At times it was even possible to walk past a puppy on the opposite side of the street and Ted would stay calm.
The cooler autumn weather brought back old habits. The nipping increased, Ted became more restless and agitated, and small gains, such as walking on a loose leash, were lost. Ted’s attention seeking and aggressive behaviour relapsed to what it had been when he first came to me. On the other hand, Ted learned “tricks” quickly and enjoyed learning as long as it occurred inside the house. When outside, Ted was nervous and anxious, constantly checking his environment for perceived threats.
Eventually I became so desperate that I decided to try the anti-anxiety medication the vet had suggested. Unfortunately, it did not improve Ted’s problem behaviours but created new ones: frequent tail chasing and nightly furious barking. Ironically, the anti-anxiety medication made Ted more anxious.
After 12 months of training and six weeks on anti-anxiety medication, I had to admit to myself that Ted’s rehabilitation was not within my power and I had a dangerous dog. Re-homing him would not have been responsible. Animal shelters euthanise large aggressive dogs for this reason. So did I.