Fear Aggression in Dogs

Fear related aggression can be a difficult and dangerous problem and typically takes time and patience to reverse. Some dogs, such as toy breeds and shepherding breeds, are more likely to develop fear responses, and sometimes aggression.

Although many fear related problems may be eased through the application of proper exercise, diet, and training, some dogs may need additional help such as antianxiety or antidepressant medications to control their actions and reach their full potential. 

Aggression related to fear can be a difficult behavioral trait to change and should be handled carefully. This is an easier disorder to prevent than to treat.

Dogs that are experiencing fear around people may express it in several ways. Behaviors that may be exhibited when a dog is afraid may include:

• Aggressive chewing
• Biting
• Cowering
• Ears held back
• Escape behaviors
• Exaggerated yawning
• Excessive vocalizations
• Holding head lower than back
• Licking nose or face (with no food present)
• Lip tension
• Nipping
• Pacing
• Panting
• “Punching” with the muzzle
• Showing the whites of the eye
• Tail tucked under
• Timidity
• Trembling
• Whites of the eye turning pink or red

Types

In some cases, aggression issues due to fear can become unmanageable with behavior modification and training methods alone. Chronic fear and aggression may require psychiatric medications to assist in treatment. Most psychiatric medications require six to eight weeks before substantial improvement is seen, although a few are relatively fast acting. The most commonly used psychiatric medications for canines include: 

Benzodiazepine Derivatives

This category of drugs includes medications such as Valium and Xanax, which are frequently effective for the temporary relief of anxiety and fear as these medications have a relatively quick action. Unfortunately, dogs often build up an immunity to the  compounds used for these treatments making them less suitable for long term usage.

Selective Serotonin Reuptake Inhibitors

Often used in canines for generalized fears and obsessive-compulsive behaviors, this category of medication includes Fluoxetine, Prozac, and Zoloft. SSRIs are one of the most frequently prescribed medication for anxiety disorders, and Fluoxetine is one of the more successful treatment methods for aggression issues. 

Tricyclic Anti-anxiety Medications

Medications such as Clomicalm and Elavil fall into this category, and are commonly used to treat both anxious and obsessive behavior in canines but may cause troubling side-effects, particularly when weaning the patient off of the drug.

Triggers that may cause fear and aggression in dogs are typically a combination of nature and nurture. Possible components to developing aggression due to fear could include: 

• Developmental Factors - Circumstances such as abuse, traumatic events, or loss of a caretaker may have more of an effect when they occur during a puppy’s developmental phase and improper socialization early in life can cause a dog to be more fearful
• Environmental Factors - Being in an environment of restriction and overcrowding such as a shelter or puppy mill may induce chronic fear in dogs that may lead to aggression; violent environments or incidents may trigger fear in canines, and in some situations may lead to the development of anxiety disorders or PTSD 
• Genetic Predisposition - Certain dogs or breeds of dog may have a slight predisposition to develop aggression due to fear; some shepherding and toy breeds may have an inherited predisposition for fear 
• Physical Disorders - Some physical disorders, particularly those that cause chronic pain, can elicit aggressive behavior in canines due to fear; other disorders with a physical basis that may lead to fear-based aggression may include bacterial or viral infections or the loss of senses such as hearing or sight

Your veterinarian will collect information for a behavioral history when you visit the clinic for a behavioral problem such as aggression. Data that is requested to complete a complete behavioral history would typically include the patient’s sex and age as well as anything else that may be known about the breed of the canine. Information about the circumstances prior to any episodes of aggression as well as how your dog’s behavior changed after the incident can also prove helpful in diagnosing any underlying disorders. 

Facts regarding any changes to diet or any new medications that have been introduced recently will also be needed as well as which corrective methods have already been tried and the result. If your veterinarian suspects a medical component to the behavior at all they will typically perform a complete physical examination as well, which will include standard diagnostic tests such as a complete blood count, biochemistry profile, and urinalysis.

Treatment for behavior issues will depend on both the severity and the underlying trigger for the behavior. Chronic aggression due to fear can be a potentially dangerous situation and should be addressed by a veterinary professional. Treatment for dogs who have shown fear related aggression should be a cooperative effort between the animal’s owners and a professional trainer or behaviorist. It is important not to scold or punish the fearful dog for its fear response. Scolding your dog for fearful behavior may actually enforce their feelings and increase the chances that fearful behavior will turn into aggressive behavior. 

One of the training methods that is commonly utilized to treat fear disorders is known as desensitization, a method in which treats and praise are used in conjunction with the presence of the object of fear to cause the feared object to become more a more positive and familiar presence and thereby reduce the fear of it. Regular obedience training may also be effective in mitigating fear and anxiety, reducing the likelihood of an aggressive response, and may be utilized to distract the dog from negative stimuli in a technique known as a counter-conditioning treatment. In some cases, behavioral therapy and training are not enough to calm the patient and anti-anxiety or anti-depressant medications, such as diazepam or Prozac, may be employed to calm your companion.

Medications given for psychological imbalances will take several weeks before their effectiveness is known, and it is essential that your veterinarian knows all of the other medications your dog is on. The way that canines metabolize this drug is very different from the way that a human metabolizes the drug and dosages will vary based on your dog’s specific response to the medication. 

Many anti-depressants and anti-anxiety medications have contraindications with certain pain medications, antihistamines, and even herbal treatments such as St. John’s Wort or Kava Kava. Medications alone are rarely effective in eliminating challenging problem behaviors, and changes to both your pet’s exercise levels and diet are often helpful in reducing problems. Continuing behavioral training will help your pet to become a happier and healthier individual.