What Tests Does Your Vet Run Before Prescribing Seizure Medication for Dogs?

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-14

Key Takeaways

• Prior to prescribing seizure medication, veterinarians conduct a thorough physical and neurological examination to assess overall health and identify potential brain or nervous system abnormalities, establishing a baseline for future comparisons.
• Comprehensive blood work, including a Complete Blood Count (CBC) and biochemistry panel, is critical to evaluate organ function (liver, kidneys), blood sugar levels, and screen for metabolic causes of seizures, ensuring safe medication metabolism and ruling out treatable conditions.
• Advanced imaging, such as Magnetic Resonance Imaging (MRI) or Computed Tomography (CT) scans, may be recommended if initial blood work is normal but the neurological exam is abnormal or seizures are atypical, to detect structural brain lesions like tumors or inflammation.
• Urgency triage is essential; immediate emergency veterinary care is required for seizures lasting over 5 minutes, multiple seizures within 24 hours, or failure to regain consciousness between seizures, while less severe or isolated events may warrant a same-day appointment.
• Owners must provide detailed seizure history, including duration, appearance, and recovery time, as this information is vital for accurate diagnosis and guiding appropriate diagnostic testing and treatment selection.
• Seizure medications are potent and require precise dosing based on individual health status and test results; never administer leftover medications or human drugs without explicit veterinary instruction due to risks of toxicity and overdose.

If your dog has just had a seizure, you are probably frightened and looking for answers. The good news is that most dogs who experience seizures can be managed safely with medication. But before your veterinarian writes that first prescription, they will usually want to run some tests. These tests are not delays or unnecessary expenses. They protect your dog from harm.

Seizure medications are powerful drugs that affect the brain, liver, and kidneys. Giving them without knowing what is causing the seizures can be risky. Some causes of seizures need completely different treatment. For example, a dog with low blood sugar needs sugar, not an anti-seizure drug. A dog with a brain tumor may need surgery or specialized care. Your vet needs information to choose the right drug and the right dose for your specific dog.

This article explains what tests your vet will likely recommend, why each test matters, and what you can expect during the visit. You will learn what the results mean and how they guide treatment. You will also learn which signs mean you should head to an emergency clinic right now, before any testing.

Is This an Emergency?

Some situations require immediate emergency care. Do not wait for a same-day appointment if your dog shows any of these signs.

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 "type": "triage",
 "title": "Urgency triage by severity of signs",
 "tiers": [
  {
   "tier": "danger",
   "label": "Go to an emergency vet now",
   "signs": [
    "A seizure that lasts longer than 5 minutes",
    "Two or more seizures within 24 hours",
    "Your dog does not fully recover consciousness between seizures",
    "Your dog has trouble breathing, collapses, or cannot stand after a seizure"
   ],
   "action": [
    "Call the nearest emergency veterinary hospital and leave immediately",
    "Do not wait to see if it stops"
   ]
  },
  {
   "tier": "warn",
   "label": "Book a same-day appointment",
   "signs": [
    "Your dog has a first-ever seizure that stops within 2 to 3 minutes and recovers fully within 30 minutes",
    "Your dog has repeated seizures but they are short and spaced days apart",
    "Your dog seems confused, wobbly, or unusually tired for more than an hour after a seizure"
   ],
   "action": [
    "Call your regular vet as soon as they open",
    "Describe what you saw",
    "They will tell you when to come in"
   ]
  },
  {
   "tier": "safe",
   "label": "Watch at home for a defined period",
   "signs": [
    "Your dog has a single, brief seizure that lasts under 2 minutes, recovers completely, and has no other symptoms",
    "This is only acceptable if your dog has already been diagnosed with epilepsy and is on a stable medication plan"
   ],
   "action": [
    "Keep a written log of the date, time, and length of the seizure",
    "Call your vet within 24 hours to report it",
    "If seizures become more frequent or longer, move to the rows above"
   ]
  }
 ]
}

If you are unsure which row fits your dog, call your vet. They can help you decide. But if the seizure is still happening when you call, hang up and go to the emergency room.

What Is Most Likely Going On?

The medical term for a seizure is a convulsion. A seizure happens when a burst of abnormal electrical activity spreads through the brain. This causes the body to jerk, stiffen, or lose consciousness. Some dogs paddle their legs, drool, or lose control of their bladder. Others stare blankly or seem disconnected for a minute or two.

The most common cause of repeated seizures in dogs is idiopathic epilepsy. The word idiopathic means the cause is unknown. In this condition, the brain itself is structurally normal, but it has a tendency to misfire. Idiopathic epilepsy usually begins in dogs between six months and six years of age. Certain breeds are more prone to it, including border collies, Labrador retrievers, golden retrievers, and beagles.

But epilepsy is not the only possibility. Seizures can also come from toxins, such as chocolate, xylitol, or certain flea products. They can come from liver disease, kidney failure, or a sudden drop in blood sugar. They can come from head trauma, brain tumors, or infections like meningitis. Your vet cannot tell which cause is at work just by looking at your dog. That is why testing matters.

The First Step: A Full Physical and Neurological Exam

Your vet will start by examining your dog from nose to tail. They will check the heart, lungs, and abdomen. They will feel for any signs of pain or swelling. Then they will do a neurological exam, which tests how the brain and nervous system are working.

The neurological exam includes checking your dog's reflexes, balance, and coordination. Your vet may watch your dog walk, test how the pupils react to light, and check whether the dog can feel its own toes. These simple tests can reveal whether the seizure came from a problem in the brain itself or from something elsewhere in the body that affected the brain.

This exam is painless and takes only a few minutes. It gives your vet a baseline. If your dog has a brain tumor or an injury, the neurological exam may show subtle signs that point in that direction. If the exam is completely normal, that supports the possibility of idiopathic epilepsy.

Blood Work: The Essential Baseline

Blood tests are the single most important step before starting seizure medication. Your vet will draw a small sample of blood from your dog's leg or neck. This takes less than a minute and most dogs tolerate it well.

The blood sample is used to check several things. A complete blood count, or CBC, looks at red blood cells, white blood cells, and platelets. This can reveal infection, anemia, or other problems. A biochemistry panel checks the liver, kidneys, and blood sugar. These organs process and clear medications from the body. If the liver or kidneys are not working well, a normal dose of seizure medication could build up to dangerous levels.

The blood work also screens for metabolic causes of seizures. Low blood sugar, called hypoglycemia, can cause seizures in dogs. So can severe liver disease, because the liver fails to filter toxins from the blood. If your vet finds one of these problems, the treatment is not a seizure drug. The treatment is fixing the underlying condition.

Your vet will also use the blood work to choose the right medication. Some seizure drugs are processed by the liver. Others are cleared by the kidneys. Knowing your dog's organ function helps your vet pick a drug that is safe and effective. The FDA's guidance on safe use of pet medications emphasizes that dosing must be precise and based on the individual animal. Your vet will determine the exact dose for your dog based on weight, health status, and test results.

Advanced Imaging: When Blood Work Is Not Enough

If the blood work is normal and your dog is young and otherwise healthy, your vet may diagnose idiopathic epilepsy and start medication. But if your dog is older than six years, if the neurological exam shows abnormalities, or if the seizures are unusual in any way, your vet may recommend advanced imaging.

The most common imaging test is magnetic resonance imaging, or MRI. An MRI uses a strong magnet and radio waves to create detailed pictures of the brain. It can show tumors, inflammation, strokes, or structural abnormalities that blood tests cannot detect. An MRI requires general anesthesia because the dog must lie completely still. This is a more involved procedure and is usually done at a specialty hospital.

A less detailed option is a computed tomography scan, or CT scan. A CT scan uses X-rays to create cross-sectional images. It is faster than an MRI but shows less detail in the brain. Your vet will recommend one or the other based on your dog's specific situation.

The American Veterinary Medical Association's pet owner resources explain that diagnostic imaging is often necessary when the cause of a neurological sign is not clear from blood work alone. If your vet recommends an MRI, they are looking for a physical cause of the seizures that medication alone cannot fix.

What Happens After the Tests?

Once the test results come back, your vet will discuss the findings with you. If the diagnosis is idiopathic epilepsy, they will explain the medication options. If the tests reveal a different cause, such as liver disease or a brain tumor, the treatment plan will be tailored to that condition.

Your vet will also explain the risks and benefits of medication. Seizure drugs can cause side effects, including drowsiness, increased thirst, and changes in appetite. Some require regular blood monitoring to make sure the levels stay in a safe range. The FDA's animal drug information notes that all approved animal drugs carry potential risks, and your vet will help you weigh those risks against the danger of uncontrolled seizures.

You should never start your dog on seizure medication without a veterinary examination and testing. Giving the wrong drug, or the wrong dose, can be dangerous. Your vet is the only person who can safely determine what your dog needs.

What You Can Do at Home Right Now

If your dog has had a seizure but is now awake, alert, and acting normally, your job at home is to keep them safe and gather information. Do not give any medication unless your veterinarian has already prescribed it for this exact situation. Do not give human medications, ever. Some human drugs are toxic to dogs, and the wrong dose of even a safe drug can cause harm.

Keep a calm, quiet space for your dog. Dim the lights and reduce noise. Offer fresh water but do not force them to drink. Let them rest. Do not put your hands near their mouth during a seizure, and do not try to hold their tongue. A seizing dog cannot swallow their tongue, and you risk being bitten.

Call your veterinarian as soon as the seizure ends. If the seizure lasts longer than five minutes, if your dog has multiple seizures in a day, or if they do not recover consciousness between seizures, this is an emergency. Go to an emergency veterinary hospital immediately.

What to Write Down Before You Call

Your veterinarian needs a clear picture of what happened. Write these things down while they are fresh in your mind:

• The date and time the seizure started
• How long it lasted, in minutes or seconds
• What your dog was doing right before it started, for example sleeping, running, or eating
• What the seizure looked like, such as paddling legs, stiffening, drooling, or loss of consciousness
• Whether your dog lost control of their bladder or bowels
• How long it took for your dog to act normal again after the seizure stopped
• How many seizures your dog has had in the past week or month
• Any new foods, treats, medications, or household products your dog was exposed to recently

Bring this written record to your appointment. It is often more accurate than trying to remember details under pressure.

What a Veterinary Visit Usually Involves

Your veterinarian will start by asking about your dog's history. Expect questions about age, breed, past illnesses, current medications, diet, and any possible exposure to toxins. They will perform a full physical exam and a neurological exam, which checks reflexes, balance, and mental state.

The most common tests before starting seizure medication are blood work and sometimes urine testing. Blood work typically includes a complete blood count, which looks at red and white blood cells, and a biochemistry panel, which checks organ function, blood sugar, and electrolyte levels. These tests help rule out causes like liver disease, kidney failure, low blood sugar, or infections that can trigger seizures.

Depending on your dog's age, breed, and exam findings, your veterinarian may recommend bile acid testing to check liver function more closely, or blood pressure measurement. If blood work is normal and seizures continue, advanced imaging such as an MRI may be recommended to look for structural problems in the brain.

Test Explanation Table

Cost Ranges: What Drives the Price

Costs vary widely by region and clinic. These are general ranges only, not quotes. Blood work alone often falls between $100 and $300. Adding a bile acids test can raise that by $50 to $150. An MRI is a major expense, often between $1,500 and $3,500, because it requires general anesthesia and specialized equipment.

The biggest cost drivers are the type of tests, whether your dog needs anesthesia, and whether you visit a general practice or a specialty hospital. Emergency visits cost more than scheduled appointments. Ask your clinic for an itemized estimate before any test is run.

When an Online Vet Can Help, and When It Cannot

Any situation involving an active seizure, a seizure lasting more than five minutes, multiple seizures in one day, or a dog that does not recover between seizures requires hands-on emergency care. Do not use a remote consultation for these. Go to an emergency hospital.

A remote consultation is genuinely useful for earlier, milder situations. If your dog had one brief seizure and is now completely normal, an online vet can help you decide whether a visit is needed today or can wait until tomorrow. They can also answer questions about medication side effects, help you track seizure frequency, and support follow-up care for a dog already on a stable treatment plan.

A remote veterinarian can take a detailed history, watch video of your dog's behavior, and advise you. In many states they can prescribe medication, but prescribing rules differ by state and some require an in-person examination first. What they cannot do is palpate the abdomen, listen to the chest, take a temperature, run bloodwork, or image the brain. Those limitations matter. Seizures have many possible causes, and without hands-on testing your veterinarian cannot know what is driving them. The US Food and Drug Administration and the American Veterinary Medical Association both emphasize that safe medication use starts with a proper diagnosis and clear communication with your veterinarian. Use remote care as a bridge, not a replacement, for in-person diagnosis.

Common Mistakes Owners Make Before and After Seizure Medication

Watching your dog have a seizure is frightening, and fear can lead to rushed decisions. Here are the most common mistakes owners make, and what to do instead.

Giving a leftover medication from another pet. A drug that helped your older dog or a friend's cat may be wrong for your dog. It could also be the wrong dose, which is dangerous. The FDA warns that dosing errors are a leading cause of medication problems in pets. Always use medication prescribed for your specific dog, at the dose your veterinarian calculated.

Stopping the medication suddenly because your dog seems fine. Seizure drugs work by keeping a steady level in the bloodstream. Stopping abruptly can trigger severe, prolonged seizures, a condition called status epilepticus, which is life-threatening. If you need to stop, your veterinarian will guide you through a gradual reduction.

Doubling the next dose after a missed one. This can cause overdose symptoms like wobbliness, drowsiness, or worse. If you miss a dose, give it as soon as you remember, unless the next dose is close. In that case, skip the missed one and continue the normal schedule. When in doubt, call your clinic.

Assuming one seizure means lifelong medication. Many dogs have a single seizure and never have another. Your veterinarian will usually recommend starting daily medication only after a pattern emerges, such as two or more seizures within a few months, or a single severe seizure.

Hiding the problem out of embarrassment or fear of cost. Seizures are a medical issue, not a behavior problem. Delaying care means your dog may seize again without protection. Most clinics can discuss payment options, and some offer care credit plans.

How to Reduce the Chance of Another Seizure

You cannot always prevent seizures, but you can lower the risk of triggers. Give medication at the same times every day, usually 12 hours apart. A phone alarm helps. Keep a steady routine for meals and sleep. Some dogs are sensitive to missed meals, which can affect drug absorption.

Avoid known triggers where possible. These can include stress, loud noises like fireworks, overheating, or certain household toxins. Keep your dog away from chocolate, xylitol, and rodent poisons, all of which can cause seizures in a dog without epilepsy.

Store medication in a cool, dry place, out of reach of children and pets. Check the expiration date regularly. If your dog vomits within an hour of getting the pill, contact your veterinarian, because the dose may not have been absorbed.

What Recovery and Ongoing Management Look Like

Seizure medication is not a cure. It is a management tool that reduces the frequency and severity of seizures. Most dogs need daily medication for life once treatment begins. It usually takes two to four weeks of steady dosing to reach a stable level in the blood, and your veterinarian may adjust the dose during this time.

You will likely have a recheck appointment about one to three months after starting. The veterinarian may repeat blood work to check liver function and drug levels. After that, rechecks often happen every six to twelve months. Many dogs on seizure medication do well for years with normal quality of life.

Some dogs become sleepy or wobbly for the first week or two as their body adjusts. This usually improves. If it does not, or if your dog seems excessively sedated, call your veterinarian. They may lower the dose or switch to a different drug.

Seizure frequency is the main measure of success. If your dog was having one seizure a month and now has one every six months, the medication is working. If seizures continue at the same rate, or get worse, your veterinarian may add a second drug or recommend further testing like an MRI.

Frequently Asked Questions

How long will my dog need to take seizure medication? For most dogs with epilepsy, treatment is lifelong. Once the medication is controlling seizures well, stopping it usually brings the seizures back, sometimes worse than before. Your veterinarian will reassess at each visit, but the expectation is daily medication for the rest of your dog's life. Some dogs with a single seizure or a clear temporary cause, like a toxin, may not need long-term treatment. Your veterinarian will base the plan on your dog's specific diagnosis and seizure pattern.

Can my dog still live a normal life on this medication? Yes, most dogs do. Many owners report their dogs are the same happy, active pets after adjusting to the medication. The first few weeks may include sleepiness or mild wobbliness, but these effects usually fade. The goal of treatment is to let your dog live without the fear and danger of frequent seizures. With regular rechecks and blood work, most dogs on seizure medication enjoy many good years.

What if my dog has a seizure while on medication? Stay calm and time it. Most seizures last under two minutes. If it goes longer than five minutes, or if your dog has multiple seizures without waking up in between, that is an emergency. Call your veterinary emergency clinic immediately. A single breakthrough seizure does not always mean the dose is wrong, but you should report it to your veterinarian, who may adjust the plan.

Will the medication damage my dog's liver? Some seizure drugs are processed by the liver, and long-term use can affect liver enzyme levels. That is why your veterinarian runs blood work before starting and again during treatment. These tests catch problems early, often before any symptoms appear. If liver values rise, your veterinarian may lower the dose, add a supplement, or switch to a different drug. Regular monitoring makes serious liver damage uncommon.

Can I give my dog CBD oil instead of prescription medication? There is not enough reliable evidence to support CBD as a replacement for prescription seizure drugs. Some owners use it alongside medication, but it can interact with other drugs and the quality of products varies widely. Talk to your veterinarian before adding anything. If you do use CBD, your veterinarian needs to know, because it can affect how the prescription drug works and how blood tests read.

What should I do if I miss a dose? Give the missed dose as soon as you remember, unless the next dose is due within a few hours. In that case, skip the missed dose and continue on schedule. Never give two doses at once. If you miss more than one dose, or if your dog has a seizure after a missed dose, call your veterinarian. They may want to see your dog or adjust the schedule. The American Veterinary Medical Association offers general guidance on working with your vet for medication questions.

Related Clinical & Scientific Guides

• What Are the Side Effects of Bravecto for Dogs? What to Watch For
• Can You Give Your Dog Human Allergy Medicine? Whats Safe
• Can You Give Your Dog Dramamine for Car Sickness?

References and Further Reading

• FDA Center for Veterinary Medicine Animal Drug Information
• FDA Safe Use of Pet Medications
• AVMA Pet Owner Resources
• MSD Veterinary Manual Pet Owner Version
• AAHA Pet Owner Resources

Related Articles

• What Are the Side Effects of Seizure Medication in Dogs?
• What Does a Vet Check for When Your Dog Needs a Heartworm Test?
• What to Expect When Your Dog Needs a Urine Test Before Starting Seizure Medication
• How Much Does a Vet Visit Cost for a Dog's Ear Infection Medication?
• What Are the Side Effects of Thyroid Medication for Dogs?

This article is general educational information for pet owners. It is not a substitute for veterinary diagnosis, examination, or treatment. If your pet is showing severe or rapidly worsening signs, contact an emergency veterinary hospital immediately.