What's Causing Your Dog's Seizures and Sudden Confusion?

If your dog just had a seizure, started walking in circles, or seems suddenly confused, take it seriously. These can be signs of encephalitis, which is inflammation of the brain. It’s not a single disease with a single fix. The cause determines everything: the treatment, the urgency, and what comes next.

If your dog is showing symptoms right now, call your vet or an emergency clinic immediately. If you’re here to understand what’s happening or what to expect, keep reading.

What is encephalitis in dogs?

Encephalitis means the brain is inflamed. Sometimes the surrounding membranes are involved too, which is called meningoencephalitis. Either way, something is causing the brain tissue to swell and malfunction, and that produces neurological symptoms that can look alarming fast.

It’s not rare, and it’s not something to watch and wait on. Brain inflammation in dogs can progress within hours, so getting to a vet, ideally a veterinary neurologist, quickly is the right move.

What are the types of encephalitis?

This is the distinction that changes everything about how your dog gets treated.

Infectious encephalitis

This is when something external gets in and directly attacks brain tissue. Common culprits include:

• Canine distemper virus: a serious viral infection, more common in unvaccinated dogs
• Tick-borne diseases: Rocky Mountain spotted fever, Ehrlichia, and others can cause brain inflammation
• Fungal infections: like Cryptococcus, especially in dogs with compromised immunity
• Bacterial infections: often spreading from a nearby source like an ear infection or bite wound
• Protozoal infections: Neospora and Toxoplasma can reach the brain

Treatment targets the infection itself, with antivirals, antibiotics, or antifungals alongside supportive care. Get the cause right, and there’s a real fighting chance.

Immune-mediated encephalitis (MUE, GME, NME)

This is where the dog’s own immune system misfires and attacks brain tissue. No outside invader. The immune system is the problem. This category is called meningoencephalitis of unknown etiology (MUE) and includes:

• GME (granulomatous meningoencephalitis): immune cells form inflammatory masses in the brain or spinal cord. Can affect any breed.
• NME (necrotizing meningoencephalitis): a more aggressive form that destroys brain tissue. Strongly associated with small breeds like Pugs, Chihuahuas, Maltese, and French Bulldogs.
• NLE (necrotizing leukoencephalitis): similar to NME but affects white matter. Seen in Yorkshire Terriers and other small breeds.

Treatment means suppressing the immune system. Corticosteroids are usually the first step, often combined with other immunosuppressants like cyclosporine or mycophenolate. Antibiotics won’t help here, which is exactly why getting the diagnosis right first matters so much.

What are the signs of encephalitis in dogs?

Neurological signs can show up suddenly or build over days. Here’s what to watch for:

• Seizures: often the most alarming and urgent sign
• Head tilt: the head tilts to one side and stays there
• Circling: walking in tight loops, usually toward the affected side
• Ataxia: wobbly, uncoordinated movement, like they’re drunk
• Behavior changes: sudden aggression, confusion, disorientation, or personality shifts that feel out of character
• Blindness: stumbling into walls or not tracking movement
• Neck pain or stiffness: reluctance to move the head, crying when touched
• Weakness or paralysis: in one or more limbs

Any combination of these is a reason to call your vet right now, not tomorrow morning.

What to do during a seizure or neurological emergency

If your dog is actively seizing or showing sudden neurological signs, here’s your plan:

• Stay calm. Your dog needs you thinking clearly.
• Don’t restrain them. You could get bitten, and it doesn’t help.
• Clear the area. Move anything they could hurt themselves on.
• Time the seizure. More than 2 to 3 minutes is a cluster seizure and a true emergency.
• Don’t put anything in their mouth. Dogs don’t swallow their tongues, and you will get bitten.
• Call an emergency vet immediately, especially if it’s a first seizure, multiple seizures in a short window, or your dog doesn’t return to normal within 10 to 15 minutes.
• Film it if safe to do so. Footage helps your vet understand what happened.

A first-ever seizure in an adult dog always warrants a vet visit, even if your dog seems fine afterward. Encephalitis can cause a single seizure before things escalate.

How is encephalitis in dogs diagnosed?

Your vet will start with a full neurological exam to figure out where in the nervous system the problem is coming from. From there, the workup typically includes:

• An MRI is the gold standard for imaging the brain. It shows inflammation, lesions, or masses that X-rays simply can’t catch.
• A spinal tap (CSF analysis) involves taking a small sample of cerebrospinal fluid, the fluid that surrounds the brain and spinal cord, and analyzing it for white blood cells, protein levels, and infectious agents. This is often how infectious and immune-mediated encephalitis are distinguished from each other.
• Bloodwork and urine tests check for systemic infection, organ function, and tick-borne disease.
• Infectious disease testing uses specific panels depending on your region and your dog’s history.

MRIs and spinal taps are almost always done together under anesthesia. It’s a significant day for your dog and a significant cost. But trying to treat without a proper diagnosis is guesswork, and with encephalitis, guesswork can cost your dog their life.

What is the treatment and prognosis for dog encephalitis?

Treatment is entirely driven by the cause.

For infectious encephalitis, targeted antimicrobials are the cornerstone, alongside supportive care. Prognosis varies widely based on the agent involved and how quickly treatment starts.

For immune-mediated encephalitis, corticosteroids like prednisone are usually the starting point, often combined with additional immunosuppressants. This is typically lifelong management, not a cure. GME can be managed long-term in many dogs. NME, particularly in Pugs, tends to carry a more guarded outlook, though some dogs do live comfortable lives with ongoing treatment.

What consistently improves outcomes across all types: getting to a neurologist fast, completing the full diagnostic workup, and not stopping treatment prematurely.

Does pet insurance cover encephalitis in dogs?

Yes, encephalitis is eligible for coverage under a Lemonade Pet accident and illness policy, as long as the condition isn’t pre-existing. That means your dog shouldn’t be showing any signs or symptoms before your policy starts or during your waiting period.

An MRI alone can run $2,000 to $4,000. Add a spinal tap, hospitalization, and months or years of immunosuppressants with regular rechecks, and the costs are real. For small breed owners, especially those with Pugs, Chihuahuas, Maltese, or French Bulldogs, the genetic predisposition to NME makes getting coverage in place early especially worth thinking about. Getting covered while your dog is healthy is what keeps those options open.

Before we go

If your dog is showing neurological symptoms right now, close this tab and call your vet or an emergency clinic immediately. This article is here to help you understand what’s happening. Your vet is the one who can actually help your dog.

For everyone else: encephalitis is one of those diagnoses that rewards fast action. Know the signs, know what to do during a seizure, and don’t talk yourself out of calling the vet if something feels wrong. Early diagnosis and the right treatment make a meaningful difference in outcomes. And if your dog isn’t already covered, now is a good time to look into it.

Frequently Asked Questions

A few quick words, because we <3 our lawyers: This post is general in nature, and any statement in it doesn’t alter the terms, conditions, exclusions, or limitations of the policies issued, which differ according to your state of residence. You’re encouraged to discuss your specific circumstances with your own professional advisors. The purpose of this post is merely to provide you with info and insights you can use to make such discussions more productive! Naturally, all comments by, or references to, third parties represent their own views, and Lemonade assumes no responsibility for them. Coverage may not be available in all states. Please note that statements about coverages, policy management, claims processes, Giveback, and customer support apply to policies underwritten by Lemonade Insurance Company or Metromile Insurance Company, a Lemonade company, sold by Lemonade Insurance Agency, LLC.  The statements do not apply to policies underwritten by other carriers.