There are many possible causes for a dog who is suddenly stumbling or falling over. Often, the particular way they are stumbling can give us clues as to why it’s happening.
Idiopathic (‘Old Dog’) Vestibular Disease
One of the most common causes for the sudden onset of falling and stumbling is idiopathic vestibular disease. This is also known as ‘old dog vestibular disease’ as it tends to affect our senior pets.
Old dog vestibular disease typically shows up suddenly, and causes a previously healthy dog to stagger and lean dramatically to one side. It is commonly accompanied by a head tilt, and classically, a flickering of the eyes back and forth (known as nystagmus).
While this condition can be very shocking to see, the good news is that it is almost always self-limiting, meaning it goes away on its own in time. Usually there is some visible improvement within 2-3 days but it can take 2-3 weeks to fully resolve.
While not a terribly common cause of falling over in dogs, ear infections (when they affect the inner ear) can sometimes affect a dog’s balance mechanism. This can happen with or without an overt infection of the outer ear canal.
Dogs with a middle or inner infection will present similar to those with ‘old dog vestibular disease’ – a head tilt and stumbling to that side are common. They may also be painful. These infections can sometimes be tricky to diagnose, requiring x-rays and sometimes more advanced imaging like CT scans.
Inflammation of the Brain or Spinal Cord
Inflammation of the brain or spinal cord are termed encephalitis and meningitis, respectively. When both occur concurrently, the term is meningoencephalitis. Unfortunately, these conditions are about as scary as they sound.
In addition to symptoms like ataxia and falling over, dogs with this kind of inflammatory disease may have a fever, decreased appetite, lethargy, and changes with their overall mentation and behavior.
Certain breeds are predisposed to encephalitis, including pugs, french bulldogs, and yorkies.
Other cases are caused by infection with viruses, bacteria, or parasites. Some well known examples would be the Distemper and Rabies viruses or the tick-borne agents that cause Ehrlichiosis and Lyme disease. These can affect any breed or age of dog.
Treatment of these cases focuses on controlling the inflammation and targeting any underlying infection.
Intervertebral Disc Disease (IVDD)
Dogs with intervertebral disc disease (known colloquially as a ‘slipped disc’) will struggle to walk and may collapse in their hind end.
In milder cases, the primary symptoms may be reluctance to walk or a hunched posture due to pain. In moderate cases, they will show abnormal limb placement and that classic ‘drunken gait’ where their limbs cross in front of each other. These are the ones who may collapse in their back legs when they try to walk. In the most severe cases, these dogs can be completely paralyzed from waist or neck down.
This condition primarily affects long backed dogs such as dachshunds and shih tzus. Treatment will depend on the severity of the condition, ranging from bed rest to surgical decompression.
Marijuana toxicity is a common cause of strange behavior and stumbling in a previously healthy pup. Dogs are exceedingly sensitive to the effects of marijuana. In addition to being wobbly on their feet, these patients are notoriously hypersensitive to stimuli and often dribble urine.
There are bedside drug tests available that your veterinarian may recommend if your dog is showing these kinds of symptoms. Fortunately, the prognosis is usually very good with supportive care.
Unfortunately, cancer has to be a consideration when we have a pet who becomes uncoordinated. This is more common in senior dog, and in the case of brain tumors, tends to come along with other symptoms as well. Dogs with brain tumors may show symptoms like walking in circles, generalized confusion, and even seizure activity.
Diagnosis often involves advanced imaging like CT scans or MRIs. More often than not, treatment is focused on palliative care (minimizing symptoms and keeping your dog comfortable for as long as possible).
Seizure or Stroke
The most common kind of seizure activity in dogs is called a ‘grand mal’ seizure. This looks like a dog who is recumbent on their side with their legs convulsing. In addition, dogs having a seizure may urinate or defecate unknowingly. Their jaw may chatter or they could foam at the mouth. Generally, they are completely unaware that this is happening.
Thankfully, typical seizure activity lasts only 30 seconds to a few minutes, though in some cases it can be prolonged. Your dog may continue to act a bit strangely as they come out of the episode, sometimes for several hours.
In young dogs, seizures are usually due to underlying epilepsy. Seizures in senior pets are more likely to be related to cancer.
Strokes are not particularly common in dogs, but if a blood clot does affect their brain, they can show a wide range of neurological symptoms. These include a head tilt, difficulty walking, blindness, and behaviour changes. Strokes are more common in dogs with underlying conditions like Cushing’s Disease or high blood pressure.