When It’s Not A Seizure: Treating Dogs with Paroxysmal Dyskinesia

During Sadie’s six months in rescue at Lab Rescue LRCP, the four year old spayed Labrador Retriever had several episodes of what appeared to be seizures. Then a month after her adoption, she had another in which she was laying down and it appeared to her pawrents that she couldn’t move normally. She was fully conscious and was able to track the owner with her eyes. She had no hypersalivation, urination or defecation. The first episode lasted seven minutes, and then about 10 to 15 minutes later she had another episode that lasted three minutes. 

In the car on the way to her primary veterinarian, she had a third episode then a fourth one during her veterinarian’s exam. She was treated with midazolam, which did not stop the episode, so she was given intravenous phenobarbital. Sadie was discharged with phenobarbital and Keppra, and was doing well with no additional episodes. She was a bit more sedate than usual after starting the phenobarbital but had no other major changes in behavior. 

Diagnosis & Treatment: Paroxysmal Dyskinesia

Sadie was referred to Veterinary Neurology and Imaging of the Chesapeake (VNIoC) by her primary veterinarian for follow-up. Dr. Julianna Mannix immediately suspected that Sadie’s “episodes” did not mimic classic idiopathic epilepsy, but rather a movement disorder called Paroxysmal Dyskinesia. 

Since epilepsy hadn’t been ruled out, Dr. Mannix kept Sadie on her seizure control medications (phenobarbital and Keppra), and prescribed an episode rescue protocol of intranasal midazolam. Dr. Mannix scheduled Sadie for a follow-up appointment in three months. In the interim, Sadie’s owners were asked to take videos of any episodes, which could help the VNIoC neurology team determine if these events were truly seizure-related or something else entirely.

Sadie’s parents shared several videos over the course of the initial three month treatment, which helped Dr. Mannix confirm that the episodes were consistent with Paroxysmal Dyskinesia rather than true seizures. At Sadie’s recheck, Dr. Mannix recommended tapering Sadie off of phenobarbital and increasing the Keppra dose to decrease the severity of the episodes.

Left: Sadie the Labrador Retriever with her adoptive family in their yard. Right: Sadie and her family visiting the Newfoundland and Labrador monument in Canada.

Her pawrents report that Sadie went from having two-hour spasm attacks every four to six weeks, to having no attacks in the past year. Since her adoption, Sadie has been busy living her best life. This “love bug” has travelled across continental North America, visiting 27 states and Newfoundland, Canada. When she is not travelling, she loves going on drives, eating, playing with her Lamb Chops, and swimming.

“We cannot thank Dr. Julianna Mannix enough for everything she has done for our Sadie. Dr. Mannix is a special person and an outstanding doctor who saved Sadie’s life and we will be forever grateful. We are truly blessed to have her in our lives.” –Sadie’s pawrents

Left: Sadie the Labrador Retriever enjoying the beach with her owner. Right: Sadie relaxing at home with her favorite Lamb Chops toys.

What is Paroxysmal Dyskinesia in Dogs and Cats?

Paroxysmal dyskinesias (PDs) are intermittent movement disorders characterized by episodes of involuntary abnormal movements that occur only during an attack — sometimes described by pet owners as a “seizure mimic” or “non-epileptic episode,” since affected pets remain fully conscious throughout. The word paroxysmal refers to the sudden onset of these episodes in an otherwise neurologically normal dog or cat, while dyskinesia describes involuntary, uncontrolled body movements.

During an episode, affected pets remain conscious and aware of their surroundings, as they do not lose consciousness or control of their mental state. Although some dogs and cats may appear unsettled or less responsive during an event, they are typically alert. Between episodes, neurological examinations are usually normal. Individual attacks may last from several minutes to a few hours, and some pets may experience multiple episodes over a short period of time.

In contrast, seizures are often associated with signs such as loss of consciousness, generalized convulsions, muscle rigidity, paddling movements, excessive salivation or foaming at the mouth, and loss of bladder or bowel control. Following a seizure, pets enter a recovery period known as the post-ictal phase. This phase may persist for several minutes to several hours, and in some cases can extend for one to two days. During this time, dogs and cats may exhibit disorientation, unsteadiness, lethargy, increased thirst or appetite, hyperactivity, or temporary vision impairment.

Ongoing Treatment for Paroxysmal Dyskinesia

Despite her increased dose of Keppra, Sadie still had frequent episodes over the next three months, so she was started on another anticonvulsant, zonisamide. At her six month checkup, Sadie was stable. At her twelve month checkup, Sadie has still not had an episode since starting on zonisamide! To ensure her ongoing wellbeing, Sadie will return to VNIoC for bloodwork every six months.

FAQ: Prognosis for Pets with Paroxysmal Dyskinesia

Is Paroxysmal Dyskinesia a lifelong condition in dogs and cats?

Yes, Paroxysmal Dyskinesia in pets is generally a lifelong, chronic condition. However, individual episodes do not shorten the pet’s normal lifespan or cause permanent damage between attacks.

Do pets stay on medications for Paroxysmal Dyskinesia forever?

No, pets do not always stay on medications for Paroxysmal Dyskinesia (PD) forever. In fact, some pets with this condition do not require medication at all.

Whether a pet needs lifelong medical management depends entirely on the frequency of their episodes, their breed, and how they respond to alternative treatments used, such as dietary adjustments.

Does Paroxysmal Dyskinesia impact a pet’s lifespan/health?

No, Paroxysmal Dyskinesia does not typically shorten a pet’s lifespan or cause long-term damage to their health. It is a non-progressive neurological movement disorder, i.e., it does not get worse over time or cause deterioration in the brain.

What’s the difference between a seizure and paroxysmal dyskinesia in dogs?

During a paroxysmal dyskinesia episode, pets stay fully conscious and alert, with neurological exams typically normal between attacks. A true seizure, by contrast, usually involves loss of consciousness, generalized convulsions, and a recovery period afterward (the post-ictal phase) that can last minutes to days.

What medications are used to manage paroxysmal dyskinesia in dogs?

Not every pet with paroxysmal dyskinesia needs medication — treatment depends on the frequency of episodes, the pet’s breed, and their response to alternative approaches such as dietary adjustments. In Sadie’s case, her veterinary neurology team used a combination of anticonvulsant medications, including phenobarbital, Keppra, and zonisamide, to manage her episodes over time.