Seizures in dogs can be a distressing experience for both pets and their owners. Understanding the different types, potential causes, and available treatments is crucial for effective management. This article aims to provide a comprehensive overview of canine seizures, drawing on expert insights and research.
What Are Seizures?
Seizures are characterized by abnormal electrical activity in the brain, leading to temporary disruptions in normal brain function. They can manifest in various ways, from subtle twitches to violent convulsions.
Generalized Seizures
The most recognized type is the grand mal seizure, also known as a tonic-clonic seizure. This involves widespread, excessive electrical activity affecting both sides of the brain. During a grand mal seizure, a dog may suddenly collapse, experience violent spasms in all four limbs, foam at the mouth, lose bladder or bowel control, and lose consciousness.
If your dog has a seizure, prioritize their safety and yours. Remove any nearby breakable items. If near stairs, position yourself below your dog to prevent further falls. Avoid putting your hands in their mouth, as they may bite unintentionally. It’s also important to remember that during the postictal phase, which can last for hours after a seizure, your dog may be disoriented and potentially exhibit aggressive behavior. Timing the seizure is critical, as prolonged seizures can lead to a life-threatening condition called status epilepticus.
Status epilepticus is defined as a continuous seizure lasting more than five minutes. This condition requires immediate veterinary intervention, often involving intravenous medication like diazepam (Valium) to stop the seizure. Prolonged seizures can cause a dangerous rise in core body temperature, which can be fatal.
Other forms of generalized seizures include:
- Tonic seizures: Characterized by stiff, extended limbs that do not jerk.
- Clonic seizures: Involve hyper-flexed, non-jerking limbs.
- Myoclonic seizures: Manifest as jerking limbs.
- Atonic seizures: Result in the dog standing, staring, and being unresponsive.
Focal Seizures
Focal seizures, in contrast to generalized seizures, originate from a localized area of abnormal electrical activity in the brain. These can present in diverse ways, such as “fly-biting,” where the dog repeatedly snaps at unseen flies, or the “chewing gum fit,” characterized by repetitive jaw clacking. Other signs might include twitching of an eyelid, lip, or ear. Crucially, consciousness is not always lost during focal seizures. While these often do not require treatment, it’s essential to monitor your dog closely, as a focal seizure can sometimes escalate into a generalized seizure.
Causes of Seizures
Seizures in dogs can stem from a variety of underlying issues:
Reactive Seizures
These are caused by metabolic disorders such as hypoglycemia (low blood sugar) or hypocalcemia (low blood calcium), liver disease, liver shunts, or kidney disease. In these cases, the brain itself is healthy, and correcting the metabolic imbalance can resolve the seizures. Certain medications can also trigger reactive seizures by lowering the brain’s seizure threshold; discontinuing the drug typically resolves these. Toxins are another significant cause, including household items like dark chocolate, caffeine, xylitol (a sugar substitute), antifreeze, rat poison, and alcohol. Eliminating exposure and providing specific treatment for the toxin can stop the seizures.
Structural Seizures
These seizures result from abnormalities within the brain itself, such as tumors, head trauma, inflammatory diseases (like meningitis), or infectious diseases such as rabies and canine distemper.
Idiopathic Epilepsy
This is the most common cause of seizures in dogs, characterized by an unknown origin. A diagnosis of idiopathic epilepsy is typically made only after all other potential causes have been ruled out. It usually begins in dogs between six months and six years of age. Dogs under one year are more prone to congenital defects, intoxication, or infectious diseases. In older dogs (over six years) experiencing their first seizure, metabolic disorders or structural brain lesions like tumors or strokes become more likely. Certain breeds, including Schnauzers, Collies, Basset Hounds, Cocker Spaniels, Labrador Retrievers, and Golden Retrievers, exhibit a higher predisposition to epilepsy.
Treatment and Management
The approach to treating seizures depends on the dog’s age, seizure history, and overall health.
Antiepileptic Drug Therapy
For dogs between six months and six years old with normal test results, veterinarians often recommend against immediate antiepileptic drug (AED) therapy after a first seizure. However, exceptions include cluster seizures (multiple seizures within 24 hours), particularly violent seizures, seizures lasting longer than five minutes, or in breeds with known difficult seizure presentations like German Shepherds, Border Collies, Irish Setters, Golden Retrievers, Siberian Huskies, Keeshonds, and Saint Bernards.
A seizure log is vital for determining when to initiate anticonvulsant therapy, based on increasing frequency, duration, and severity. Starting medication prevents potential, though not guaranteed, seizure-free futures. It’s important to note that even with medication, breakthrough seizures can occur. You can explore average dog boarding cost if you need to consider care options.
Commonly prescribed first-choice AEDs include phenobarbital, levetiracetam (Keppra), zonisamide, and potassium bromide. Zonisamide and levetiracetam are often favored for their efficacy and minimal side effects. If a dog experiences refractory epilepsy (seizures that don’t respond well to initial treatment), requiring more than one AED, levetiracetam is frequently used as a second medication. The extended-release formula, Keppra XR, offers more convenient twice-daily dosing compared to the short-acting levetiracetam, which requires three daily doses.
Other Veterinary-Recommended Therapies
- Rectal Diazepam or Intranasal Midazolam: Your veterinarian may prescribe diazepam for rectal administration or midazolam for intranasal application at home to shorten or lessen the severity of seizures.
- Pulse Keppra Therapy: For dogs prone to cluster seizures while on an AED, levetiracetam can be kept on hand for use immediately after a seizure to prevent clustering.
- Adjunctive Therapies: Gently stimulating the vagal nerve by applying pressure to the dog’s closed eyelids for 10-60 seconds may help reduce seizure duration and severity, potentially even averting a seizure if recognized in its pre-ictal phase.
- Traditional Chinese Veterinary Medicine (TCVM): Acupuncture and herbal remedies under a TCVM specialist can improve seizure control, especially in cases of refractory epilepsy, and may help reduce AED dosage.
- Prescription Diet: Purina Pro Plan Veterinary Diet NeuroCare (NC) is a specialized diet containing medium-chain triglycerides (MCTs) that have shown promise in reducing seizure activity in epileptic dogs.
Managing seizures requires a collaborative approach between pet owners and veterinarians. By understanding the potential causes and treatment options, owners can provide the best possible care for their canine companions. Emergency dog boarding near me might be a consideration if you need immediate assistance.