Neurologic disorders occur mostly in dogs and cats. Common conditions among dogs include epilepsy, tumors, disc disease and paralysis, and canine cognitive dysfunction (dementia). Muscular dystrophy can occur in dogs, but it's rare as breeders have weeded it out. Certain breeds of dogs, including German and Australian shepherds and Labrador retrievers, are particularly susceptible to epilepsy. During seizures, they typically lose consciousness and collapse. Their limbs become stiff or rigid, and they usually drool and may lose bowel or bladder control. These seizures can last 30 seconds to a minute.

Vets recommend care based on the dog's age and breed and the underlying cause. They may order diagnostic tests or refer owners to a specialist to determine the cause, which could be epilepsy, encephalitis (inflammation in the brain from infection or disease), or a tumor. Seizures are less common in cats, but they also should be evaluated by a vet or at an emergency clinic.

Dogs also can have strokes. Signs include sudden dizziness, sluggishness, balance problems, paralysis, loss of bladder or bowel control, head tilt, impaired vision, or an inability to use one side of the body. If an underlying condition, such as kidney disease, caused the stroke, treating that condition makes another stroke less likely. Dogs may develop a disorder like multiple sclerosis (MS), with symptoms such as seizures, behavioral changes, and balance and walking problems. MS is diagnosed with an MRI and an analysis of the pet's spinal fluid.

When dementia occurs in dogs, it's usually after age 12. They may exhibit changes in their sleep pattern, lose bowel or bladder control, be disoriented and anxious, no longer recognize familiar faces, or stop displaying typical behaviors.

Dachshunds and French bulldogs can experience paralysis and disc disease when an intervertebral disc slips and pushes on the spinal cord or nerve root. Surgery is often recommended, especially if the dog can still feel its feet, which the veterinarian determines by pinching the paw hard enough to elicit a response. If a dog can feel that, it has a very good chance of recovering.

Meningiomas, a type of tumor that develops in the thin protective tissue that covers the brain, are fairly common in cats, especially older ones. The tumors are usually benign, but if they grow, they can cause pressure on the brain. In general, cats do well with meningiomas. A more problematic tumor is a glioma, which can appear in the brain or spinal cord. Veterinarians may suggest surgery to remove the tumor if it's accessible. Otherwise, they may recommend radiation, but not chemotherapy, as it typically does not cross the blood-brain barrier.

Cats also can have neurologic disorders like feline panleukopenia and hydrocephalus. Feline panleukopenia is a highly contagious viral disease caused by the feline parvovirus. Symptoms include listlessness, vomiting or diarrhea, and a dull and rough coat due to dehydration. The condition can't be cured, but cats can live with it. Hydrocephalus is a buildup of fluid that enlarges the skull and compresses the brain. It causes trouble with walking and seeing. In some cases, vets can drain the fluid, and the animal may improve. In other cases, the fluid can't be drained, or the damage is too extensive already.

A virus called feline infectious peritonitis can cause seizures and walking and balance problems. Cats can get ear infections, which in rare cases can break through the skull and can involve the brain, resulting in severe balance problems. If an ear infection is caught early, a full recovery is expected.

Email your vet about anything odd in your pet. Include a photo or video, if possible. If your pet collapses and loses consciousness, go to an emergency clinic. When pets are diagnosed with neurologic conditions, vets need to know if they have any other diseases. They'll ask how you want to proceed. Vets usually recommend a spectrum of treatment, so if you don't want an MRI—for example, when epilepsy is suspected—vets will likely prescribe medication to control the seizures.

If a vet suggests testing, ask what information it will yield, how much it will cost, and whether euthanasia may be appropriate.

Dr. Carrera-Justiz is clinical associate professor of neurology at the University of Florida College of Veterinary Medicine in Gainesville. She is board-certified in neurology by the American College of Veterinary Internal Medicine.