Understanding the Hidden Health Conditions That Can Increase Aggression in Dogs
Dogs are often referred to as ‘man’s best friend.’ However, it is important to recognize that even the most loving and well-behaved pets can exhibit aggressive behavior if they are suffering from certain health conditions. Vets have highlighted that a range of hidden health issues can lead to aggression, making it crucial for pet owners to be aware of the signs and seek appropriate veterinary care.
Neurological Conditions
Several conditions that affect a dog’s brain or nervous system can cause changes in behavior. For instance, dogs with epilepsy may become more aggressive after a seizure. According to Southfields Veterinary Specialists, a very small number of dogs might display aggression following a seizure. If this occurs, it is essential to stay away from the dog and ensure they are in a safe space until they recover.
A sudden spike in aggression could also indicate a brain tumor. Apex Vets explains that one of the first signs of a brain tumor in dogs is a noticeable shift in behavior, which may include aggression, confusion, or anxiety. In older dogs, a surge in aggression could be a sign of dementia, which can make them feel threatened or anxious in previously normal situations.
Pain-Related Conditions
Pain is one of the most common causes of aggression in dogs. Shauna Walsh, PDSA Veterinary Nurse, highlights several conditions linked to pain, including traumatic injuries such as wounds, broken bones, or even a broken claw, arthritis, and dental disease. She emphasizes that any changes in a dog’s behavior, especially sudden aggression, should prompt an immediate visit to the vet.
Behavior changes are sometimes one of the earliest signs that a dog may be feeling unwell or in pain. A vet can check for any medical causes behind the behavioral change. Any health problem that causes pain, discomfort, confusion, or general illness can lower a dog’s tolerance and make them more likely to react aggressively.
Hormonal Imbalances
Hormonal imbalances can also increase irritability in dogs. Hypothyroidism, a condition where the thyroid gland does not produce enough hormones, can lead to changes in behavior, including increased irritability and aggression. This can manifest as uncharacteristic growling, snapping, or even biting towards people or other animals.
Cushing’s disease, caused by the overproduction of cortisol, can also lead to increased aggression around food. It is important to monitor your dog for any signs of hormonal imbalance and consult a vet if you notice any changes in behavior.
Infectious Diseases
Several infectious diseases can cause sudden or increased aggression in dogs. Rabies is one of the most well-known, with two forms: ‘dumb rabies’ and ‘furious rabies.’ The latter can cause a spike in aggression. Unfortunately, there is no treatment for rabies once symptoms develop, and it is nearly always fatal.
Canine Distemper is another infectious disease that can cause drastic personality changes in dogs. This virus invades the brain, leading to behavioral changes like sudden aggression, fear, or confusion.
Vision or Hearing Loss
The loss of certain senses can make dogs feel threatened, leading to a surge in aggression. Cataracts, which cloud the lens of a dog’s eye, can make it difficult for them to see clearly, potentially causing anxiety or confusion. Deafness can also occur in dogs of any age and for various reasons, affecting their ability to perceive their surroundings.
Medication Side-Effects
Certain medications prescribed to dogs for various health and behavior issues can contribute to or exacerbate aggressive behavior. Drugs that affect brain chemistry, such as corticosteroids, some anticonvulsants, and pain medications, can increase irritability or impulsivity in dogs. It is important to be aware of these potential side effects and discuss them with your vet.
Signs Your Dog Is About to Attack
If you notice any of the following signs in your dog, it may indicate that they are about to attack:
- Lifting their lip or baring their teeth
- Staring intently
- Growling or snarling
- Snapping
- Lunging
Early Signs to Look Out For
According to Shauna Walsh, learning what is normal for your dog is one of the most important steps in preventing aggression. Dogs rarely bite without warning, but some of the warning signs are very subtle and can be easily missed.
Subtle signs your dog is feeling uncomfortable include:
- Yawning when not tired
- Turning their head away
- Licking their lips
- Looking away from you or showing the whites of their eyes
- A tense, lowered body
- Their tail tucked underneath their body
- Lifting a front paw
- Trembling or shaking
If these signs are missed, they may progress to signs of aggression, such as lifting their lip or baring their teeth, staring intently, growling or snarling, snapping, or lunging.
Responding to Aggressive Behavior
If you do notice any of these signs in your dog, it is important to respond accordingly. Bryony Francis, Head of Clinical Behaviour at the RSPCA, advises removing the cause of the fear—particularly if it’s a child, another person, or another pet—or encouraging the dog to move somewhere they’ll feel safe and calm.
By being vigilant and understanding the underlying causes of aggression in dogs, pet owners can take proactive steps to ensure their furry friends remain healthy and happy. Always consult a veterinarian if you notice any changes in your dog’s behavior.
