Two Spaniels and a Baby
Predation and Pharmacological Fixes
Humanity’s true moral test . . . consists of its attitudes towards those who are at its mercy: animals.
The woman at the other end of the phone line sounded as if she were at the end of her rope. “My name is Robin,” she said in a shaky voice. “My local vet said you might be able to help. My dog is trying to go after my new baby, and to tell you the truth, I’m very scared.”
The situation, and the woman’s desperate tone, prompted me to take her very seriously. “Tell me exactly what’s going on.”
When she had brought her newborn back from the hospital a few days before, she had sat on the couch cradling her new darling. Her husband, Barry, brought in the couple’s two English springer spaniels to meet the new addition to the family.
“Samson, the male, wriggled with excitement and ran across to see me,” Robin recalled. “Then he began whimpering and whining and got into a frenzy. There was no controlling him. He started to bark at the little bundle and mouth at the bedding. Barry had to take Samson outside.”
“Has the dog displayed more signs of unruly and unsettling behavior toward the baby?”
“He’s definitely not getting better,” Robin replied. “We tried putting him in the basement, and he just barked and barked until the neighbors complained. When we put him outside, he actually attacked the vinyl siding of the house, and tore through a screen door trying to get inside.”
I told her it was vitally important to keep pets and baby separate and instructed her to bring the dogs in to see me the next day.
Samson and his female housemate, Delilah (of course), were beautiful, normally obedient dogs. But during our consultation, they told me tales of Samson’s predatory impulses, such as the time he snapped up a friend’s parakeet, not releasing the poor bird until Barry pried open the dog’s jaws.
While at my office, Samson and Delilah were the picture of sweetness. But I wanted to see how the dogs behaved in their home environment, so I visited the residence the next day. There I witnessed what I considered a dangerous situation. When the baby cried, the dogs became agitated. Delilah ran to the bedroom where the crib was, put her paws up on the side, and began weaving and jumping as if searching for something. When Robin placed the baby down, both dogs started to whine and wriggle, pushing themselves against the crib. They were on a mission. Samson’s whining rose to a crescendo.
“You have to keep the baby and the dogs completely apart,” I said. The male dog was the primary offender in the situation, and Delilah was simply piggybacking on his aggression. So I counseled thirty minutes of aerobic exercise every day for the dogs and a change in diet to a strict, nonperformance ration. Even though both dogs were well trained, I ordered a crash refresher course of obedience sessions.
“We will work on a program of gradual introductions between Samson and the baby. We’ll reward him for remaining calm and direct him when he begins to lose control. But, outside of these periods, separate the dogs and baby.”
During my initial visit, we conducted a training session designed to acclimate the dogs to the presence of a new addition to the household pack. I waited in the bedroom where the baby was in her crib and Robin brought both dogs in on a leash. They were agitated and whining. I instructed Robin to give them commands such as, “Sit” and “Lie down.” Samson and Delilah both obeyed but continued to whine.
“What do I do now?” Robin asked.
“Just take the dogs out of the bedroom and get them under control in the living room.”
We regrouped away from the infant to consider our options. Perhaps we could remove Samson from the scene by farming him out to Robin’s in-laws for a few days, to separate the two dogs and break the predatory cycle. Also, since I confirmed that Samson was showing a predatory response, I would prescribe a course of medication, either the antidepressant amitriptyline or buspirone, which I thought might have some antipredatory action via their effect on serotonin.
Robin and Barry proceeded to follow my advice. They took Samson to their in-laws, retrained and exercised them as I suggested, and began a regimen of treatment with buspirone. The combination was a success on trial visitations. Without consulting me, they brought Samson back into their home after a couple weeks, and he remained calm even when the baby wailed—formerly a sure trigger for his anxious behavior. Robin called me, gushing about the miraculous change.
But when the medication was discontinued after one month, Samson regressed to his old infant-threatening ways. I sternly ordered full-scale safety measures and another course of buspirone. Once again, Samson’s behavior improved. This time, after another two months of medication, he was weaned off the drug with no resumption of his old predatory habits. My long-term follow-up indicated that Samson and Delilah both had finally accepted the new creature as a member of their pack, to be protected and cherished rather than considered potential prey.
Predatory aggression is another fully functional, absolutely normal, and reasonable type of aggression. Reasonable, unless you are the prey, that is. Dogs, like cats and humans, are a predatory species and behaviors for hunting and killing are hardwired in a brain region called the lateral hypothalamus, which regulates appetite and leads to the procurement and consumption of food. Unlike other forms of aggression, the predatory kind does not involve malice or anger. It’s just business as usual for a predator on the go. Nothing personal, says the lion to the antelope. The appetitive phase precedes the consummatory phase as surely as spring comes before summer.
House cats perform a mini-me example of a lion’s attack. Their predatory aggression is sometimes referred to as the “quiet biting attack.” They stalk, crouch, chatter their teeth, and finally run and spring on unsuspecting prey. Their intent is to kill and then devour the prey. But the killing is not done malevolently or in defense. It doesn’t involve anger or fear. It’s not aimed at imposing their will. It is simply the functional means to a necessary end, which is staying alive.
Modern domestic dogs don’t need to hunt and kill prey, but they often do so anyway. Some dog breeds with strong prey drive—most terriers, for example—are still prized for their ability to find and kill rodents.
My sister Angela had a German shepherd who liked to chase squirrels. We wondered what the dog would do if she ever caught one. The answer came one day when a squirrel she was chasing got caught up in a tennis net in her backyard. Dog and squirrel came face to face in a standoff. Neither moved for a few seconds, but then the squirrel leaped at the dog’s face and bit her in the nose. Big mistake. The squirrel immediately became an ex-squirrel!
Herding breeds also have high prey drive, but the difference is that it’s mostly restricted to the appetitive phase, because the consummatory phase of predation was bred out of them years ago by their handlers. Sheepherding dogs who killed and ate their charges were culled and dispatched. That artificial selection has, over time, produced sheep dogs who will do no more than merely nip at sheep.
High prey drive in animals sometimes “dyslexes”—that is, it fixates erroneously on nonprey subjects. Most terriers and sheep dogs, for example, are avid ball chasers. Sometimes, however, that high prey drive is misdirected in unacceptable ways. Dogs may chase running children, joggers, skateboarders, and cyclists. In a few extreme cases, as with Robin and Barry’s springer spaniels, dogs view an unfamiliar crying infant as wounded prey, and move in as if for the kill. It is vital that new parents introduce a baby to the family dog under close supervision.
Movement of any kind is a strong trigger for predatory behavior. Dogs often go after passing cars and trucks, which is dangerous for both drivers and animals. I knew of a farmer who crafted a dangerous homemade solution to the problem. He tied a bandanna to the wheel hub of his own car, then drove it repeatedly past the vehicle-chasing pooch (at moderate speed only). The dog would pursue the car, seize the handkerchief in its teeth, and get rolled head over tail. The farmer’s tough-love approach broke the animal of car chasing forever, but it could as easily have killed his dog.
Vets prefer a kinder, gentler, more instructive approach. In that regard, a head halter works well. We have owners of car-chasing dogs stand by the roadside with their pet on a leash, head halter in place, and wait for a car or truck to roll by. As the dog starts its shenanigans, we have the owner say, “No” or “Leave it!” as they apply gentle but steady upward tension to the leash until the dog quits. Pressure on the dog’s muzzle is thought to replicate a mother dog’s correction of her young, so it is biologically appropriate. It works, though the tactic may have to be repeated a few times on different days until the dog realizes that the owner’s word is law.
Pet dogs have no need to hunt and kill, because they’re fed by their owners. But because prey drive is so deeply embedded, dogs still may express predatory outbursts. It is truly instinctive. Dogs with high prey drive who are not properly exercised will be more likely to engage in annoying predatory behaviors. Those not given appropriate outlets for their instinctual drives sometimes resort to dangerous attacks. Terriers, who were bred to hunt and kill vermin, can be entertained by earth trials, in which they traverse man-made underground tunnels. Their quarry is often a varmint-scented cloth, though sometimes it’s a live rat or rabbit in a protective underground cage. In organized barn hunts, dogs search among bales of hay for live rats safely housed in indestructible little cylinders. The rules for humane treatment and protection of the rats used in such trials are (quite rightly) longer than the rules of the game. Shepherd-type dogs can be enrolled in fly-ball classes, or entertained for hours at home with a Chuckit! and a tennis ball. Sight hounds revel in lure coursing. Sporting breeds and scent hounds enjoy tracking.
These activities are not merely occupationally enriching games. They also help fulfill natural hunting instincts and create a happier, healthier, more biologically satiated dog. Such dogs are better and safer house pets.
Cats also enjoy the opportunity to expend their energies, too, focusing on such safe prey as feathered wands or laser mice. Those who don’t may resort to what is called a vacuum behavior, in which they act out their instincts by chasing and pouncing on imaginary prey. They are, so to speak, all dressed up with no place to go: equipped with a predatory drive, but with no real quarry in sight. There are numerous indoor toys for cats to exercise on and interactive games for hunting balls, stuffed mice, and other objects.
Some forms of aggression seem to defy classification and treatment. Some may have a genetic origin. Others may simply be normal behavior with the brakes off. We can learn a lot from atypical cases, which can teach us about why and how aggression arises. Investigating the extremes, we can test the limits of what is normal.
One case we had recently at Tufts involved a male Malinois, a short-haired version of a Belgian shepherd that in appearance resembles a German shepherd. The Malinois displayed violent aggression toward his male owner, and before we got involved, bit off half his owner’s forefinger. The affected pooch did not respond to any of the usual treatments, strategies that included avoidance, making the dog “work” for all food and treats, and various medications.
Because the dog was unresponsive, we had to dig deeper. Searching the literature, we became aware of a particular genetic glitch in this breed, recently discovered at the UC Davis veterinary school. The culprit seemed to be a faulty dopamine transporter gene, which suggested that trazodone, an old-fashioned antidepressant that can reverse the glitch, might work. We tried it and some desensitization exercises—bingo! Aggression no more.
We had learned from this single, particularly instructive case that behavior modification alone may not always be sufficient to extinguish aggression. Because I’d been trained as an anesthesiologist, in my early career as a behaviorist I naturally turned to medication as a solution to intractable behavior problems involving aggression. At the time, many of the available pharmacological options produced unacceptable side effects such as hyperactivity, or were sedating to the point that the animal was asleep much of its life. Valium, for example, can be addictive and also often has paradoxical results, meaning that it could sometimes trigger the precise behaviors we were trying to prevent, including causing excitement or even increased aggression. I did not want to turn to popular progesterone-like synthetic hormones, either, because they cause unacceptable side effects, such as increased thirst and appetite, hair loss, depression, lethargy, and even cancer.
So I had to look elsewhere for new solutions to decreasing and managing aggression. Something was fueling the fire of aggression, and I wanted to find out both what was kindling it as well as how to douse the flames. To this end, I made diagrams of the pathways and interactions between various neurotransmitters, brain chemicals that convey messages, searching for the points at which a medication might achieve an antiaggressive effect.
All roads led to serotonin, the brain chemical with mood-stabilizing effects. Serotonin is a “neuromodulator.” Serotonin causes a spectrum of effects in the brain but in terms of aggression, the more serotonin is present, the less aggression is expressed. Very low serotonin levels are associated with depression and with high levels of aggression. This includes the ultimate form of self-directed aggression in humans—suicide. Robust levels of serotonin are associated with confidence, enhanced social behavior, and reduced aggression. Excess levels of serotonin cause anxiety, as is sometimes seen when a patient is exposed to too high a dose of a serotonin-enhancing drug too quickly.
Amid this welter of indicators, I needed to determine a “Goldilocks” level of serotonin-enhancing drugs to resolve issues of aggression—not too hot, not too cold, just right. All I had to do was figure out which drugs I could safely give to dogs, cats, and other animals, medications that would augment or tweak brain serotonin systems without “going over the top” to achieve my goal of reducing aggression.
My early attempts at treating aggression medically were not as successful as I would have liked, because at the time, the only drugs that were readily available were tricyclic antidepressants. So called because of their three-ringed structure, tricyclics were some of the earliest medications developed to combat depression. These drugs increase serotonin levels between nerve cells by preventing upstream cells from reabsorbing it, thus keeping it at a stable level. Theoretically, this stabilizes mood.
Unfortunately, tricyclic antidepressants also tend to elevate levels of norepinephrine, an excitatory brain chemical, which runs counter to reducing aggression. Increasing norepinephrine may be beneficial when treating pure depression, but higher levels may also lead to aggressive outbursts.
A few dogs that I treated with Elavil, a brand name for an early tricyclic officially called amitriptyline, actually became more aggressive, so I of course discontinued that drug for treating aggression and focused instead on a more serotonin-specific tricyclic antidepressant called Anafranil, a brand name for clomipramine. Despite a few drawbacks, this drug was the stand-out option. Clomipramine enhanced serotonin levels but had much less of an effect on other neurochemicals. In cases where behavior modification alone wasn’t helping, I started to include clomipramine in the treatment regimen.
One aggressive dog I saw was a young Rottweiler who was aggressive to his owner. When clomipramine was added into the mix of behavior modification therapy, the aggression practically disappeared. The owner was overjoyed to have his dog behaving normally and affectionately again. Case solved, right?
Not quite. The owner called a few weeks later to report that his dog had demonstrated odd behavior when on a walk and wondered if it could be a side effect. The Rottie had frozen on the sidewalk outside his house, trembling and salivating. I thought that he may have been having a partial seizure, which is certainly possible with clomipramine, though uncommon. Most side effects, including seizures, are dose-related so that was something to consider. This dog was on a regimen 50 percent above the normal dose because the situation was so severe and life-threatening in more ways than one. It may have had the seizure coming on anyway, with or without medication, but to be cautious, I gave the owner two options: stop giving the medication or reduce the dose. Because the treatment was so successful, there was no way this owner was going to give up on it, so he opted to reduce the dose. Fortunately, the dog did not have another freezing attack on the lower dose, and the aggressive behavior did not return. We’d found the Goldilocks dose level.
Soon after successfully treating the Rottweiler and other aggressive dogs, I began to try another serotonin system modifying drug, buspirone, to treat aggressive dogs and cats. Single-dose buspirone had already been proven as an acute antiaggressive measure in vervet monkeys on the Caribbean island of St. Kitts. These monkeys were notoriously aggressive and to study how a drug might reduce their reactivity, scientists first established how they responded to being (gently) prodded with a pole. They hated it and reacted aggressively. Well, who wouldn’t? But when the monkeys were given buspirone three hours before the prodding, they took the provocation in stride, barely reacting.
Neither clomipramine nor buspirone produced long-term sedation, a common negative side effect with other psychotropic medications. Both are considered “smart drugs,” substances that produce the desired effect with minimal collateral damage. Other purer serotonin-enhancing drugs such as Prozac—the commercial name for fluoxetine—became widely available and more affordable a few years after my early cases of aggressive dogs, so I included them in treatments. Fluoxetine worked well to reduce aggression in dogs, cats, horses, and even a parrot or two. Serotonin-selective drugs like fluoxetine were clearly superior to clomipramine, and I could use them along with buspirone if necessary. Over time, fluoxetine became more and more the treatment of choice across the veterinarian community. Our pets officially joined the so-called Prozac Nation.
In a recent case, I used a one-two combination of Prozac and Buspar, not so much for fear-based aggression as abject terror. A young adult German short-haired pointer, Lita, refused to leave the Boston apartment of her owners. The trigger for her behavior was unknown. She might have been traumatized by some scary noise while she was out walking. In any event, fluoxetine alone did not cut it, so I added buspirone. The result was a spectacular success. Lita pranced down the corridor to the elevator, as happy as she had ever been to go out. No more balking, no more struggles to get her out for a walk. Just a happy dog and happy owners. The final outcome was even better. After about three or four months, I was able to discontinue the medications and the improvement to Lita’s behavior remained. I call this effect “pharmacologic desensitization.” If subjects experience a situation without fear many times, they are able to learn that it’s safe and nonthreatening.
I continued to root around in canine brain circuitry, looking for ways to prevent aggressive outbursts. Because neurotransmitters are instrumental in triggering the fight-or-flight response in animals, I searched for ways to block the action of pro-aggressive brain chemicals. If I could impede even some of their effects, I figured I could reduce the agitation and mental foment that often precedes aggressive behavior. I thought that perhaps a beta-blocker called propranolol might work, since it blocks some of the effects of a neurotransmitter called norepinephrine, but it turned out to help my animal patients only slightly and only in some cases.
Despite my standing concerns about using drugs in the Valium family because of their side effects, I cautiously started to employ them to treat aggression. I used Valium itself, which is a brand name for diazepam, as well as related medications, alprazolam and clonazepam, which are marketed as Xanax and Klonopin respectively. Through trial and error, and working out how a particular animal might react to a drug, I got some good results in reducing aggression, especially in aggressor cats.
A pair of constantly feuding cats came to see me at Tufts. The conventional first level of treatment is to separate and gradually re-introduce them to each other—called systemic desensitization. This can click the reset button for the relationship, but since they’d become entrenched in their warfare, I also tried various medications to facilitate peaceful interactions between the pair. Nothing worked. These feline fighters were displaying territorial aggression: they had dug in and were not open to detente.
It might take two cats to tango, but one of the pair clearly danced the part of the lead aggressor. After almost a year of trial and error, I tried Xanax to reduce the bully cat’s anxiety and aggression. It worked! Since then Xanax has come to the rescue in placating other angry cats, especially those who do not care for another housemate.
In even more persistent cases of aggression, I resorted to using heavy-duty antipsychotic medications, including Haldol, the brand name for a dopamine blocker called haloperidol. Simply put, dopamine acts as the chemical connection between thought and action. Without sufficient levels of dopamine in our systems, we slow down and have movement disorders, as in Parkinson’s disease. With no dopamine in our systems at all, we become immobile, the sad condition of the patients described in one of Oliver Sacks’s books, Awakenings.
When we block dopamine with drugs such as haloperidol, animals become less aggressive, but the side effects are unacceptable, and include a reduction in activity level and strange movement disorders called dyskinesias. Human patients who take strong antipsychotic drugs for schizophrenia or manic depression for a long period can develop these involuntary grimaces and jerky large-muscle movements, or dyskinesias, as can dogs and horses, although animals generally do not show bizarre facial contortions as people do because they lack the same facial muscle structure and innervation.
I treated an aggressive Doberman with a dopamine blocker and warned the owner that she might see a dyskinesia in the form of head bobbing. I guess I wasn’t clear enough that this side effect is a bad thing and she should stop the medication if it happened. A couple weeks later she called to say that her dog’s behavior problem was much improved, but that the animal was now head bobbing.
“Why haven’t you discontinued the drug?” I asked.
“But you told me that’s what might happen!” she replied. Of course, I had her halt the medication immediately. The head bobbing stopped, fortunately, and the aggressive behavior returned, unfortunately, but we moved on to treat it with the logical next choice, a serotonin-enhancing drug, which worked for this Dobie.
I wasn’t the only one working on the pharmacological control of aggression in clinical patients. The psychiatrist Dr. John Ratey treated, among others, violent human offenders in Medfield State Hospital, Massachusetts. In a talk at Tufts Department of Psychology, Dr. Ratey discussed the types of medications he used, and I was gratified to hear they were almost identical to the ones I had come up with on my own. Dr. Ratey used antidepressants, like clomipramine, to treat aggression in people, as well as desipramine, an older tricyclic drug. In a subsequent appearance on the TV news show, 20/20, one of Dr. Ratey’s desipramine patients said he wished he had been treated earlier, before his wife divorced him, before his children stopped speaking to him, and before people at work dreaded seeing him entering the building.
Dr. Ratey also spoke highly of buspirone, and Valium-type drugs. The beta-blockers he used to treat his aggressive human patients seemed to help by reducing tension in muscles, something like a pharmacological back massage, rather than acting primarily on the brain. Dr. Ratey found this out by giving his patients a beta-blocking drug that does not cross into the brain. The medication still worked.
After the talk, Dr. Ratey and I chatted about the similarities between responses to medication in my veterinary patients and his human ones. We found that we spoke the same language; we agonized together about the lack of any formal antiaggressive treatment for man or animals.
There are almost a million aggravated assaults in the United States each year, a number that does not include instances of violent rape and murder, but aggression is not even formally recognized as a condition in the Diagnostic Manual of Psychiatry. There is no medication formally recognized or FDA-approved to treat aggression. That’s because drug companies do their best to avoid what they see as “unnecessary” risks of lawsuits.
One example of an aggressive dog who did very well with behavior modification paired with pharmacologic treatment was Lucky, a castrated male Walker hound mix. When he was two years old, he had been found wandering the streets, severely emaciated and with several broken ribs. Adopted out of a shelter, he quickly exhibited fear aggression toward people and other dogs.
Lucky would lunge, bark at, and try to bite anyone who approached him, including his owner’s mother and brother who lived in the same house. He had also attacked two other dogs who lived in the home, a cocker spaniel and a Rottweiler. Lucky also chased passing cars, a situation that got so bad the new owner couldn’t walk him on the street.
As I worked with Lucky, I taught the owner the importance of avoiding triggers. We switched the dog to a Gentle Leader type of head halter, which applies pressure to the back of the head and under the throat, not the neck. In general, animals are more easily controlled by the head than by the neck. I also instigated a behavior-modification program that was basically opposite to the one that had worked for my dog Rusty, to whom I’d given free food and treats to boost his confidence. For Lucky, instead, the motto became “Nothing in life is free.” Lucky had to work for every piece of food, for every pat on the head, and even for his freedom. I advised his owner to get Lucky a close-fitting antianxiety wrap, to increase his exercise, and to set clear boundaries of acceptable behavior.
Things improved a bit, but not enough, and his owner considered euthanasia. Lucky had bitten the owner’s brother and they all worried he’d harm someone else. I couldn’t let that happen.
Lucky’s life was on the line. I started him on Prozac as a mood stabilizer and also prescribed an “as needed” dose of clonidine, a new treatment for aggression that I had borrowed from human medicine, which works by reducing the release of norepinephrine (the excitatory hormone) in the brain. This could temper Lucky’s fight-or-flight response in particularly challenging circumstances.
The results were encouraging and, six months later, Lucky’s owners reported a 50 percent reduction in his aggressive behavior. I wanted even more improvement, so we upped the dose of Prozac. This finally did the trick. One month after the increase, Lucky was able to go to doggie day care, he no longer attacked the family or the family Rottweiler and spaniel, and even played with them occasionally. The formerly fearful and aggressive dog was now very trusting of his owners, and he even allowed strangers to approach him.
It took a period of trial and error to discover the proper treatment for Lucky, as it does with many dogs—and for people. There is no “one size fits all” when it comes to behavioral pharmacology. My motto is, “Nothing works all the time,” a guiding principle that has stood the test of time. It’s humbling to acknowledge that the brain is a very complicated place and no one knows all of its mazes and interconnections enough to predict exactly what adjustments are necessary in aggression cases—or any other behavior case for that matter.
Training was crucial to Lucky’s rehabilitation. The combination of training and medication saved his life. Prozac has saved the lives of millions of people, and I was glad that we had jumped the species barrier with it and had saved Lucky’s life—and would go on to save others.