Levetiracetam (Keppra) for Cats: Uses, Dosage & Side Effects

This information is for educational purposes only. Never give your pet any medication without your veterinarian's guidance. Dosing, frequency, and safety depend on your pet's specific health profile.

Levetiracetam, often known by the brand name Keppra, is an anticonvulsant medication used to help control seizures in cats. It is a human medication that your vet may prescribe off label in feline patients, which is common and legal in veterinary medicine when a medication is considered appropriate for the situation.

This medication works in the brain to reduce abnormal electrical activity linked with seizures. In cats, it may be used by itself or combined with another antiseizure medication, depending on seizure type, frequency, and your cat's overall health. One reason vets often consider levetiracetam is that it has minimal liver metabolism, which can make it a useful option for some cats who need an alternative or add-on to other seizure medications.

Levetiracetam is available in immediate-release tablets, oral liquid, and injectable forms. Immediate-release products are most commonly used at home. Extended-release tablets exist, but they must stay whole and are not practical for many cats because splitting or crushing them can change how the drug is released.

Levetiracetam is used most often to help manage seizures and epilepsy in cats. Your vet may prescribe it for cats with recurrent seizures, suspected idiopathic epilepsy, structural brain disease, or seizures that continue despite another medication already being on board.

In some cats, levetiracetam is chosen as a first medication when your vet wants a drug with a relatively wide safety margin and fewer liver concerns. In other cats, it is used as an add-on medication when phenobarbital or another antiseizure drug is not giving enough control on its own.

It may also be used in hospital settings for cluster seizures or status epilepticus, especially in injectable form. Even when it works well, the goal is usually seizure control rather than a cure. Your vet will look at the whole picture, including seizure frequency, recovery time, other diseases, and your ability to give medication on schedule.

Levetiracetam dosing in cats is individualized by your vet. A commonly referenced immediate-release starting range is 20 mg/kg by mouth every 8 hours, with broader published veterinary ranges of about 20-60 mg/kg every 8 hours depending on response and the clinical situation. Because the drug has a short half-life of about 3 hours, timing matters. Late doses can increase the risk of breakthrough seizures.

If your cat is taking phenobarbital at the same time, your vet may need to adjust the levetiracetam plan because phenobarbital can increase levetiracetam metabolism. Cats with kidney disease may also need extra caution because levetiracetam is cleared mainly through the kidneys.

Do not change the dose, skip doses, or stop levetiracetam suddenly unless your vet tells you to. Abrupt withdrawal can trigger seizures. If your cat is prescribed an extended-release tablet, it should not be crushed, split, or chewed. If pilling is difficult, ask your vet whether a flavored liquid or compounded form is appropriate, since formulation choice can affect both cost range and how reliably the medication is absorbed.

Many cats tolerate levetiracetam well, but side effects can still happen. Reported feline side effects include sleepiness, incoordination, drooling or hypersalivation, and decreased appetite. Some cats seem a little quiet or wobbly when first starting the medication or after a dose increase.

More serious concerns are less common, but you should contact your vet promptly if you notice persistent vomiting, sudden behavior changes, severe weakness, trouble walking, or worsening seizure activity. Any facial swelling, hives, or breathing trouble should be treated as an emergency.

Because seizure medications are often long-term, it helps to keep a simple log of dose times, seizure episodes, appetite, and any unusual behavior. That record can help your vet decide whether your cat is adjusting normally, needs a dose change, or should switch to a different treatment option.

Levetiracetam has fewer drug interactions than some older seizure medications, but interactions still matter. The most important veterinary interaction is with phenobarbital, which can increase levetiracetam metabolism and may mean your vet needs to use a different dose or dosing frequency.

Other medications that can add to sedation or neurologic depression should be used carefully together. VCA also advises caution with central nervous system depressants and notes potential caution with NSAIDs. That does not mean these combinations are always unsafe, but it does mean your vet should know about every prescription, over-the-counter medication, supplement, and herbal product your cat receives.

Before starting levetiracetam, tell your vet if your cat has kidney disease, is pregnant or nursing, or is already taking other antiseizure medications. Never assume a human liquid is safe for cats without checking first, because some formulations may contain ingredients that are not ideal for pets.