Keppra for Dogs: Side Effects and Effectiveness

Name: Keppra for Dogs: Side Effects and Effectiveness
Creator: Dr. Zubair Khalid

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-10-03

Keppra (levetiracetam) is an antiseizure medication that veterinarians use in dogs, often alongside another drug when seizures are not fully controlled. Most dogs tolerate it well, and the keppra for dogs side effects owners notice most often are sleepiness and unsteady walking. It can help reduce seizures in some dogs, but results vary, and it rarely works as a solo treatment for hard-to-control epilepsy.

This article is educational and is not a substitute for veterinary diagnosis or treatment.

Quick Answer

Keppra is commonly added to an existing seizure medication when seizures are not well controlled on that drug alone [1].
The most common side effects are sedation and ataxia (wobbliness or a drunk-looking walk), and many dogs adjust over the first few weeks.
It is cleared mainly through the kidneys, so your veterinarian may check kidney values before starting and during treatment [1].
Never change the dose or stop Keppra on your own. Stopping seizure medication suddenly can trigger a seizure cluster.
Call your veterinarian the same day if your dog cannot stand, seems overly sedated, or has more seizures than usual.

What Is Keppra and Why Do Veterinarians Use It?

Keppra is the brand name for levetiracetam, a prescription antiseizure drug. In veterinary medicine it is used most often as an add-on (adjunctive) medication for dogs with idiopathic epilepsy, meaning epilepsy with no identifiable underlying cause [1].

Vets reach for it in a few situations. Some dogs keep having seizures even on a first-line drug like phenobarbital, and adding a second medication can improve control. Other dogs cannot tolerate higher doses of their original medication, so a second drug lets the vet keep the first dose lower. Keppra is also used in emergency settings for cluster seizures and status epilepticus, which are situations where seizures come in rapid succession or will not stop.

One reason vets like it is that it has a favorable pharmacokinetic profile and limited liver metabolism [1]. Many seizure drugs are processed by the liver and can affect liver enzymes over time. Keppra is handled differently, which makes it a useful option for dogs whose liver is already under stress from another medication.

How Does Keppra Work?

Levetiracetam works in a way that differs from older seizure medications. It binds to a specific protein in the brain that helps regulate how nerve cells release signaling chemicals. By calming that release, it lowers the chance that a burst of abnormal electrical activity will spread into a full seizure.

This mechanism is part of why it pairs well with other drugs. If your dog is on phenobarbital, which works through different pathways, the two medications can target seizures from more than one angle.

Dosing Basics: Who Decides and How It Is Given

Your veterinarian calculates the dose from your dog's weight and health, and sets the schedule. There is no single dose that fits every dog. The exact amount and how often it is given depend on whether Keppra is being used for long-term control or as an emergency treatment.

Keppra comes as tablets, as a liquid, and as a compounded product. In an emergency, a veterinarian may give it intravenously. A compounded intranasal form has been studied in healthy dogs, and a single 30 mg/kg intranasal dose reached peak blood levels in about 2.3 hours, with a half-life of about 3.6 hours [2]. That research is about healthy dogs, not dogs in the middle of a seizure, so it does not tell us how well the nasal route works in a real emergency.

A few practical points:

Give the medication at the times your vet sets. Keppra is often dosed two or three times daily because it leaves the body fairly quickly.
You can usually give it with or without food, but follow your vet's instructions.
If you miss a dose, do not double up. Call your veterinary clinic for guidance on what to do.
Do not stop the drug abruptly, even if your dog seems fine. Sudden withdrawal can trigger seizures.

If your dog also takes other medications, ask your vet how to space them out. You can read about other common drugs in our guides to gabapentin side effects in dogs and Cerenia side effects in dogs.

Keppra for Dogs Side Effects: What to Expect

Most side effects are mild and tied to the nervous system. Sedation and ataxia are the ones owners report most. Many dogs look sleepy or a little clumsy for the first days to weeks, then improve as their body adjusts.

Here is a breakdown of what to watch for.

Side effect	How common or serious	What to do
Sleepiness or sedation	Common, usually mild	Keep the first few days calm. Call your vet if your dog is hard to wake.
Ataxia (wobbly walk, stumbling)	Common, usually mild	Block stairs and slippery floors. Call your vet if your dog cannot stand or walk.
Reduced appetite	Possible	Offer small, tempting meals. Call your vet if your dog stops eating for more than a day.
Vomiting or diarrhea	Possible	Call your vet if it lasts more than a day or comes with lethargy.
Behavior changes (irritability, restlessness)	Less common	Note what you see and tell your vet at the next visit, or sooner if it is severe.
Kidney changes	Not confirmed in short-term studies	Your vet may monitor kidney values, especially with long-term use [1].
Serious allergic reaction (facial swelling, hives, trouble breathing)	Rare	This is an emergency. Go to a veterinary hospital now.

A four-week study of 12 dogs with idiopathic epilepsy who were already taking phenobarbital and had levetiracetam added found no statistically significant changes in kidney markers such as SDMA, creatinine, BUN, phosphorus, or albumin [1]. That is reassuring for short-term use, but it does not rule out problems over months or years, and it does not apply to every dog. Because levetiracetam is eliminated mainly through the kidneys, dogs with existing kidney disease need closer monitoring [1].

If your dog is on multiple medications, keep a simple log of doses, seizure dates, and any side effects. That record helps your vet fine-tune the plan. Our article on probiotics for dogs and gut health side effects covers another area owners often ask about when their dog is on long-term medication.

How Effective Is Keppra for Dogs?

This is the question most owners really want answered, and the honest answer is that it depends on the dog.

Keppra is widely used as an add-on antiseizure medication because of its favorable pharmacokinetic profile and limited liver metabolism [1]. That tells you why vets choose it, but it does not tell you how many dogs improve. Response rates vary, and some dogs improve a lot while others see little change.

For dogs with drug-resistant epilepsy, seizure control is hard to achieve with any single medication. Research into why some dogs respond to treatment and others do not is still ongoing [3]. If your dog falls into the refractory group, your vet may combine medications, adjust doses, or discuss other options.

One area under study is the gut-brain connection. A three-month study of probiotic supplementation in dogs with epilepsy found a reduction in both the number of seizures and seizure days [3]. The improvement was not explained by changes in gut Lactobacillus levels or plasma GABA, and the GABA to L-glutamate ratio dropped significantly only in dogs whose seizures responded to medication, not in the drug-resistant group [3]. This is early research, and probiotics are not a replacement for antiseizure drugs, but it is an active area of veterinary investigation.

Cannabidiol (CBD) is another option some owners ask about. A review of CBD in small animal practice noted that recent studies suggest it may reduce seizure frequency in refractory epilepsy, though results remain variable [4]. Mild adverse effects such as gastrointestinal upset and sedation have been reported in dogs, and increases in serum alkaline phosphatase activity have been repeatedly seen, with unclear clinical significance [4]. If you are considering CBD, talk to your vet first. It can interact with other medications and is not a substitute for prescribed treatment.

Who Should Not Take Keppra and What Interacts With It

Keppra is not right for every dog. Your veterinarian will weigh the risks and benefits, and some situations call for extra caution.

Dogs with kidney disease. Since levetiracetam is cleared mainly through the kidneys, impaired kidney function can change how long the drug stays in the body [1]. Your vet may adjust the dose or monitor kidney values more closely.
Dogs with known sensitivity to levetiracetam or its ingredients.
Dogs on multiple antiseizure drugs. Combining medications can increase sedation and wobbliness. Your vet will adjust doses to limit this.
Pregnant or breeding dogs. Safety in canine pregnancy is not well established. Tell your vet if your dog is pregnant, nursing, or intended for breeding.

Drug interactions matter. Because levetiracetam is not heavily metabolized by the liver, it has fewer interactions than some older seizure drugs, but interactions are still possible. Always tell your vet about every medication, supplement, and over-the-counter product your dog takes, including CBD, probiotics, and joint supplements. If your dog takes heart medication, our guide to Vetmedin side effects in dogs explains what to watch for with that drug.

Overdose: What to Do

If your dog gets into the pill bottle or receives too much Keppra, act quickly. Signs of overdose can include extreme sedation, difficulty standing, vomiting, and unusual behavior.

Call your veterinarian or an emergency veterinary hospital right away. You can also contact the ASPCA Animal Poison Control Center at (888) 426-4435 or the Pet Poison Helpline at (855) 764-7661. Both may charge a consultation fee.

Do not wait for symptoms to appear. Bring the medication bottle with you so the veterinary team knows exactly what was taken and how much. Do not try to make your dog vomit unless a veterinarian tells you to.

Limitations and When to Contact a Veterinarian

No medication works the same way in every dog, and seizure control is often a process of trial and adjustment. Your veterinarian needs to see your dog and review the full history to make decisions about Keppra.

Contact your veterinarian the same day if:

Your dog is much sleepier than usual or is hard to wake.
Your dog is stumbling badly or cannot walk without support.
Your dog vomits, has diarrhea, or refuses food for more than a day.
You see more seizures than usual, or seizures that look different.

Go to an emergency veterinary hospital now if:

A seizure lasts longer than a few minutes.
Your dog has two or more seizures in a row without fully recovering in between.
Your dog has trouble breathing, facial swelling, or hives.
Your dog cannot stand or seems unresponsive.

Schedule a routine visit if:

You want to discuss whether the dose is working.
Your dog has been stable and needs a medication refill or blood work.
You are considering adding another treatment, such as CBD or a probiotic [4][3].

Frequently Asked Questions

How long do Keppra side effects last in dogs?

Most sedation and wobbliness improve within the first one to two weeks as your dog adjusts. Some dogs stay a little sleepier on the medication long term. If side effects are severe or getting worse instead of better, call your vet.

Can I give Keppra to my dog without seeing a vet?

No. Keppra is a prescription medication, and the dose depends on your dog's weight, kidney function, and other medications. Giving the wrong amount can cause serious sedation or leave seizures uncontrolled.

Does Keppra cure epilepsy in dogs?

No medication cures epilepsy. Keppra is used to reduce how often seizures happen and how severe they are. Some dogs improve a lot, others only a little, and many need more than one medication.

Can Keppra be stopped suddenly?

No. Stopping any antiseizure medication abruptly can trigger a seizure cluster or prolonged seizure. If your vet wants to change or stop the drug, they will give you a plan to taper it safely.

Is Keppra safe for dogs with kidney disease?

It needs extra care. Levetiracetam is eliminated mainly through the kidneys, so dogs with kidney problems may need a different dose or closer monitoring [1]. Tell your vet about any known kidney issues before starting treatment.

References

Short-Term Renal Effects of Add-On Levetiracetam in Client-Owned Dogs with Idiopathic Epilepsy Receiving Phenobarbital: A Four-Week Prospective Study. Veterinary sciences, 2026.
Single-Dose Pharmacokinetics of Intranasal Levetiracetam in Healthy Dogs. Journal of veterinary pharmacology and therapeutics, 2026.
Effect of Lactobacillus supplementation on seizure control, gut microbiota, and blood neurotransmitters in dogs with idiopathic epilepsy. Research in veterinary science, 2025.
Cannabidiol in small animal practice: current evidence, clinical applications and practical recommendations for dogs and cats. The Journal of small animal practice, 2026.