Immediate-release levetiracetam (Keppra) is an antiepileptic medication that helps control seizures for dogs and for cats. It’s actually a medication that’s approved for people, but vets often prescribe it for pets too. Levetiracetam comes as tablets and a liquid solution. It’s usually given to pets three times per day. The specific dosage your pet needs depends on their weight. Dogs and cats can get sleepy as a side effect of levetiracetam.
Levetiracetam is an antiepileptic medication, which means it helps with seizures.
We don’t know exactly how levetiracetam works to manage seizures. But experts think it blocks certain chemicals in the brain to calm down brain activity. This can help prevent seizures from happening.
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Aggressive or angry
change in personality
chills
crying
deep or fast breathing with dizziness
delusions of persecution, mistrust, suspiciousness, or combativeness
false or unusual sense of well-being
feeling of unreality
general feeling of discomfort or illness
headache
hoarseness
irregular heartbeat
irritability
joint pain
loss of appetite
lower back or side pain
mental depression
muscle aches and pains
numbness of the feet, hands, and around the mouth
painful or difficult urination
quick to react or overreact emotionally
rapidly changing moods
restlessness
sense of detachment from self or body
shaking
shivering
sleepiness or unusual drowsiness
stuffy or runny nose
sweating
trouble sleeping
unusual tiredness or weakness
vomiting
Less common
Bloody nose
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
clumsiness or unsteadiness
discouragement
dizziness or lightheadedness
double vision
feeling of constant movement of self or surroundings
feeling sad or empty
increase in body movements
loss of bladder control
loss of memory
mood or mental changes
outburst of anger
pain or tenderness around the eyes and cheekbones
problems with memory
redness or swelling in the ear
seizures
sensation of spinning
shakiness and unsteady walk
shakiness in the legs, arms, hands, or feet
tightness of the chest
trembling or shaking of the hands or feet
trouble concentrating
unsteadiness, trembling, or other problems with muscle control or coordination
Incidence not known
Attempts at killing oneself
being forgetful
bleeding gums
blistering, peeling, or loosening of the skin
blood in the urine or stools
bloody, black, or tarry stools
blurred vision
changes in vision
coma
confusion
dark urine
difficulty with moving
fast heartbeat
fever with or without chills
general feeling of tiredness or weakness
high fever
increased thirst
indigestion
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
light-colored stools
muscle pains or stiffness
pains in the stomach, side, or abdomen, possibly radiating to the back
pale skin
pinpoint red spots on the skin
red skin lesions, often with a purple center
red, irritated eyes
skin rash, encrusted, scaly, and oozing
sores, ulcers, or white spots on the lips or in the mouth
stomach pain, continuing
swelling of the face, ankles, or hands
swollen glands
swollen joints
thoughts or attempts at killing oneself
trouble with balance
twitching, twisting, or uncontrolled repetitive movements of the tongue, lips, face, arms, or legs
uncontrolled jerking or twisting movements of the hands, arms, or legs
uncontrolled movements of the lips, tongue, or cheeks
unexplained bleeding or bruising
unusual bleeding or bruising
upper right abdominal or stomach pain
yellow eyes or skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Loss of strength or energy
muscle pain or weakness
tender, swollen glands in the neck
trouble swallowing
unusual weak feeling
voice changes
Less common
Body aches or pain
burning, dry, or itching eyes
change in the color of the skin
congestion
cough increased
Incidence not known
Hair loss or thinning of the hair
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
No need for regular blood tests to check medication levels and safety by itself
Low risk for serious side effects
Also available as a fruit-flavored liquid for pets that have trouble swallowing pills
Give levetiracetam to your dog or cat three times a day. You can set a reminder on your phone to help you remember. It’s important not to miss a dose because the medication can wear off and make it more likely for your pet to have a seizure. Be sure to stay on top of refills so your pet doesn’t run out of medication.
You can give levetiracetam with or without food. If your pet doesn’t seem to feel well after taking the medication on an empty stomach, give levetiracetam with some food next time to help.
Levetiracetam can make your pet sleepy, which might lead them to drink less water. This raises their chance of getting dehydrated. Keep track of how much water your pet is drinking so you can catch dehydration early. Watch for signs of dehydration like panting when they haven’t been using a lot of energy, thick saliva, or a dry nose.
Let your veterinarian know if your pet starts having more seizures while taking levetiracetam. After several months, your pet’s body can get used to the medication and it might not work as well. If that happens, your vet will probably raise your pet’s dose to help control seizures better.
Tell your vet if your pet has trouble swallowing the levetiracetam tablets. They might change the prescription to a fruit-flavored liquid form of the medication.
For the liquid form of levetiracetam: Keep the liquid at room temperature. And only measure the dose using an oral syringe or dose cup from the vet’s office or pharmacy. Don’t use household spoons because they can come in many different sizes, and it’s important for your pet to get the right amount of medication.
Some pets need to take phenobarbital and levetiracetam together to keep seizures controlled. If your pet needs both, the vet might adjust the levetiracetam dose. This is because phenobarbital can lower the levels of levetiracetam in the body, which can make it work less well.
If your pet is pregnant, talk to your vet about the risks and benefits of giving levetiracetam. We don’t know if this medication is safe for pregnant dogs or cats. But studies suggest that it might harm babies of other animal species when given during pregnancy. Your vet might want to follow up more often to check on your pet.
Also talk to your vet if your pet is nursing. Your vet can talk to you about whether it’s safe for your pet to nurse while they’re taking levetiracetam.
Levetiracetam can cause some serious health issues. This risk might be even higher for certain pets. If this worries you, talk to your veterinarian about other options.
Risk factors: Stopping levetiracetam suddenly
Pets can be at risk of having seizures if they suddenly stop taking levetiracetam. This happens because if the amount of medication in their body drops too fast, it might not control their seizures well anymore.
Make sure you time refills for levetiracetam so your pet doesn’t run out of medication. Always talk to your vet before you stop giving this medication to your pet. They’ll give you instructions on how to stop the medication safely.
Risk factors: Previous behavior problems
Watch your pet for behavior changes while they’re taking levetiracetam. Although uncommon, it’s a possible side effect of the medication for pets.
In one study, some dogs had worse aggression, attention-seeking behavior, and higher energy when taking levetiracetam. Other dogs wandered around aimlessly or had signs of anxiety or depression. But some owners also noticed positive changes in their dog’s behavior, such as a calmer mood. In another study, some cats had more energy and were more alert after taking the medication.
Talk to your vet if you notice any unusual, worrisome behavior your pet starts showing while they’re taking levetiracetam.
A study showed that dogs with kidney problems had a higher risk of side effects when they took levetiracetam. These side effects included being sleepier, having problems walking, and having an upset stomach. Their blood tests also showed signs that their kidney problems might’ve gotten worse.
Tell your veterinarian if your pet has kidney problems. The vet might decide to prescribe a lower dose of levetiracetam to keep your pet safe. Also be sure your pet stays hydrated. Not drinking enough water can cause dehydration, which can hurt the kidneys or make kidney problems worse. Call a vet if your pets seems to be having too many side effects from levetiracetam.
The dose will depend on your pet’s weight. The typical starting dose for dogs and cats is 20 mg/kg by mouth three times a day (usually every 8 hours).
Your vet might raise your pet’s dose every 2 weeks based on how the medication works to control seizures. Your vet will also adjust the dose depending on any side effects.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
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