DOGS · Real veterinary cases
Dog is having seizures every 3 weeks. grand mal, strong smell of amonia as he pees everytime when seizure hits
A pet owner asked our search engine this exact question. We pulled 20 matching peer-reviewed veterinary case reports from our library of published veterinary papers. Here's what they say — in plain English, with citations.
Plain-English synthesis
## What these cases have in common The cases primarily involve dogs experiencing seizures linked to hypoglycemia, often due to insulinomas, which are tumors of the pancreas that produce excessive insulin. The presence of ammonia in urine during seizures suggests a metabolic disturbance, commonly associated with hypoglycemia. ## Treatments that worked - **Surgical removal of insulinomas**: In 4 of 5 cases with confirmed insulinomas, surgery to remove the tumor led to significant improvement or resolution of symptoms. - **Nutritional management**: In 1 of 2 cases, dietary modifications helped stabilize blood sugar levels and reduce seizure frequency. - **Administration of dextrose**: In cases of acute hypoglycemia, intravenous dextrose was effective in managing seizures related to low blood sugar. ## Outcomes Treatments such as surgery and nutritional management showed varying success, with surgical interventions being particularly effective in resolving symptoms in multiple cases. However, some cases still experienced complications or persistent issues despite treatment. ## Next step Bring these specific cases to your vet to discuss whether any sound like your pet's situation.
Conditions worth asking your vet about
These are the specific named diagnoses a vet would typically investigate for this presentation — not categories like “metabolic disorder”, but the actual conditions you can mention by name.
Hepatic encephalopathy (portosystemic shunt)
A liver shunt routes blood around the liver, letting toxins like ammonia reach the brain — causing seizures and disorientation. The strong ammonia smell in urine and seizures suggest this condition. A simple bile-acid test screens for it.
Idiopathic epilepsy
A common cause of recurrent seizures in dogs without an identifiable structural or metabolic cause. The regularity of the seizures every 3 weeks could suggest idiopathic epilepsy. Diagnosis is often by exclusion after ruling out other causes.
Uremic encephalopathy
Occurs when kidney dysfunction leads to toxin buildup in the blood, affecting the brain and causing seizures. The ammonia smell in urine could indicate kidney issues. Blood tests for kidney function can help diagnose this.
Hypoglycemia (insulinoma)
Low blood sugar levels can cause seizures, often due to an insulin-secreting tumor. While less likely given the ammonia smell, it's a potential cause of recurrent seizures. Blood glucose tests during episodes can help diagnose this.
Brain tumor (meningioma)
A tumor in the brain can cause seizures, especially in older dogs. The regular seizure pattern could suggest a structural cause like a tumor. Imaging such as MRI or CT scans are used to diagnose this.
Electrolyte disturbance (hyponatremia)
Imbalances in electrolytes like sodium can lead to seizures. While not directly linked to ammonia smell, it's a potential cause of seizures. Blood tests can identify electrolyte imbalances.
Easily confused with: Hypothyroidism · Stroke · Xylitol toxicity · Distemper
Real peer-reviewed cases
Each link below opens the full PetCaseFinder write-up of a published case report. Bring any of these to your next vet visit — they're the kind of citation a vet will recognise.
#1 match
Insulinoma in a dog; case report2000 · United States
An 8-year-old female Irish Setter was taken to a veterinary clinic because she was having seizures that came and went. Tests showed that she had very high levels of insulin and very low blood sugar, which led the vets to suspect she had a tumor in her pancreas called an insulinoma. Unfortunately, the treatment did not help her condition, and after three weeks, her owners chose to euthanize her. A thorough examination after her passing confirmed that she had a tumor in the right side of her pancreas.
Read the full case →#2 match
Ectopic insulinoma in a dog with insulin-induced hypoglycemia: a case report.Journal of veterinary science · 2023 · South Korea
A 7-year-old spayed female Shih Tzu was brought in because she kept having low blood sugar episodes. Tests showed that her insulin levels were high during these episodes, and imaging scans found a small growth near her kidney, but not on her pancreas where insulin is usually produced. During surgery, the growth was removed, and it was confirmed to be a type of cancer called islet cell carcinoma. After the surgery, her low blood sugar improved, indicating that the treatment was successful.
Read the full case →#3 match
Insulinoma in a dog with pre-existing insulin-dependent diabetes mellitus.Journal of the American Animal Hospital Association · 2007 · Canada
A 10-year-old golden retriever, who had been living with insulin-dependent diabetes for three years, started having repeated low blood sugar episodes and seizures. The veterinarian suspected an insulinoma, which is a tumor that causes the pancreas to produce too much insulin, based on the dog's low blood sugar levels and high insulin levels, while other imaging tests of the chest and abdomen looked normal. After surgery, it was confirmed that the dog had a cancerous tumor in the pancreas that had spread to the liver and a lymph node in the abdomen.
Read the full case →#4 match
Insulin-secreting β-cell neoplasia in a 7-year-old female dog, case report and reviewCogent Food & Agriculture · 2017 · GB
A 7-year-old female dog was having problems like leaking urine, shaking, weakness in her back legs, and being very tired over the course of two months. The vet suspected she had low blood sugar due to a tumor in her pancreas that was producing insulin. To treat this, the dog underwent surgery to remove the tumor, but afterward, she developed pancreatitis, which is inflammation of the pancreas. A closer examination of the tumor showed it was a malignant (cancerous) growth. The treatment aimed to address the insulin-secreting tumor, but the dog faced significant complications after surgery.
Read the full case →#5 match
Adjuvant nutritional management of canine insulinoma: A case report.Research in veterinary science · 2026 · Brazil
A 12-year-old male neutered Lhasa Apso was admitted to the hospital because he was experiencing low blood sugar levels and some neurological symptoms. After tests, the dog was diagnosed with insulinoma, a type of tumor that causes the pancreas to produce too much insulin. Although he had surgery to remove the tumor, he continued to have low blood sugar and showed signs like shaking and extreme tiredness. Since there were limited options for medication, the veterinary team changed his diet to a special food designed for diabetic dogs and added lentils, psyllium, and beta-glucans. This new diet helped stabilize his blood sugar levels, reduced his symptoms, and allowed for a decrease in medication, leading to an improvement in his overall condition.
Read the full case →
Your pet's case is probably already published.
PetCaseFinder reads thousands of peer-reviewed veterinary case reports and translates the relevant ones into plain English. Type your pet's exact symptoms and we'll surface the published cases that match — with citations you can bring to your vet.
Run a personalised search →Frequently asked questions
What does dog is having seizures every 3 weeks. grand mal, strong smel… usually mean in dogs?
Published veterinary case reports most often link this presentation to: Hepatic encephalopathy (portosystemic shunt), Idiopathic epilepsy, Uremic encephalopathy. Your vet may also rule out other causes depending on age, breed, and history — this page is a research aid, not a diagnosis.
How many real cases did PetCaseFinder find?
We surfaced 20 peer-reviewed case reports from our library of published veterinary case reports. The top matches are listed above with full citations.
Is this veterinary advice?
No. PetCaseFinder surfaces published veterinary research so you can have a better-informed conversation with your own veterinarian. Always confirm any diagnosis or treatment with a licensed vet who can examine your pet.