Anxiety
Anxiety can include several different things from separation anxiety to fear. Anxiety is when your dog becomes overly stressed and cannot emotionally deal with these stresses. It can be triggered by past trauma or bad experiences. Most dogs that experience severe anxiety can be given medications, either natural or prescription, to help alleviate their anxiousness. In some cases, a professional canine behaviourist may also be able to help you work with your dog to ease their anxiety.
Liver Disease
It may seem odd to include liver disease as a potential cause of your dog’s pacing, but damage to the liver can cause abnormal neurological behaviors which include pacing and sudden changes in behavior. When the liver is not functioning right it cannot filter toxins out of the body. These toxins can then invade the bloodstream and affect the neurological system of your dog.
Cushing’s Disease
Cushing’s disease is the overproduction of the hormone cortisol. It is most common in older dogs, but can still affect dogs of any age. The most common symptoms of Cushing’s disease include pacing, wandering and restlessness as well as panting and an increased thirst. Cushing’s disease can be caused by a pituitary tumor that can press against the brain or brain stem and cause neurological damage. This is a serious condition that will require on-going treatment.
Dementia
Dogs can develop 'doggy dementia' or canine cognitive dysfunction in their old age. The symptoms of dementia will come on slowly and you may not notice them at first. Your dog may become disoriented or confused and this can cause them to pace, wander or circle aimlessly. This is a degenerative disease.
Brain Tumor
Older dogs are more prone to developing tumors in the brain or along the brainstem causing abnormal behavior. These tumors will affect the neurological system and cause your dog to pace and seem unsettled.