Phenobarbital for Dogs: A Comprehensive Guide

Phenobarbital for Dogs: A Comprehensive Guide
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No one said that being a pet parent was always going to be rainbows and butterflies. In fact, the responsibility of being a doting dog mom or dog dad can sometimes feel impossibly difficult, particularly when your fur baby isn’t doing well. One of the hardest things that a dog owner can experience is witnessing their four-legged companion have a seizure. Watching your dog convulse and knowing that there is nothing you can do other than attempt to keep them comfortable and wait it out is heart-wrenching… to say the least.

If your pup has recently had their first seizure, there are important things you must know before beginning medication. It is only natural that you would want to jump on the first medication available in order to ensure that your dog doesn’t have to experience another episode. However, we urge you to take a moment to understand the risks associated with nearly every conventional anti-seizure medication.

In this article, we will discuss a common anticonvulsant drug known as Phenobarbital. Knowing all there is to know about your dog’s disorder and the means to treat it is imperative before making a decision that could ultimately change their life forever.

Phenobarbital for Dogs & Potassium Bromide for Dogs

What is Phenobarbital for Dogs

One of the most commonly prescribed drugs used to treat seizure disorders and epilepsy is known as Phenobarbital. The medication can be prescribed either by itself or in conjunction with another drug, depending on the severity and frequency of the seizures. Phenobarbital comes in tablet, oral liquid, capsules, or injectable form.

You may also hear your vet refer to Phenobarbital as  Luminal or Barbita.

What is Potassium Bromide for Dogs

Potassium bromide is another anticonvulsant drug that veterinarians often prescribed in conjunction with Phenobarbital. Additionally, veterinarians will often prescribe Potassium Bromide as a replacement for Phenobarbital in dogs who do not react well to the drug or who are drug-resistant.

Phenobarbital for Dogs

Why Use Phenobarbital for Dogs

When it comes to conventional medications for dogs, many times you’ll find that one medication is used to treat a slew of ailments. This isn’t the case for Phenobarbital.

Dog Seizures

Phenobarbital is primarily used as an anticonvulsant. It aims to reduce the frequency and severity of seizures in dogs. (More on dog seizures in a moment!)


In some cases, Phenobarbital is used as a sedative, although it’s not considered common. The medication is typically solely prescribed to epileptic dogs.

Dog Seizures: Understanding The Disorder

The medical definition of seizures is an uncontrolled electrical activity in the brain. The short-term derangement of normal, healthy cognitive function will often result in physical convulsions, thought disturbances, secondary symptoms, or a mixture of symptoms. You’ll also hear the term epilepsy used when describing repeated seizure episodes.

Studies are continuing to prove that seizure disorders and epilepsy are becoming an unsettling epidemic amongst our four-legged friends. In fact, experts believe that up to 5% of all dogs suffer from seizures. Therefore, it is so important for information on the disorder and associated medication to be readily available. The more you know about your dog’s condition, the better equipped you will be to making sure they are treated appropriately.

What Causes Dog Seizures

In large part, the cause of epilepsy in dogs is relatively unknown. In many cases, experts will identify what they refer to as idiopathic epilepsy. When it comes to idiopathic epilepsy, specialists can confirm that the disorder inherited, but the root cause is still unclear. In these cases, because the cause is unknown, total prevention is not possible.

However, in other cases, seizures may develop due to an underlying disease or environmental issue. These possibilities include:

  • Kidney failure
  • Liver disease
  • A tumor in the brain
  • Trauma to the brain
  • Electrolyte irregularities
  • Stroke
  • Anemia
  • Toxicity (i.e. poisoning)

It is imperative that the underlying cause of the seizures is investigated. Your vet should check for liver and kidney function as well as perform exams to rule out any issues in the brain. Additionally, blood tests will likely be done in order to confirm toxicity is not causing the seizures to occur.

Dog Seizure Symptoms

If you are unsure of whether or not your dog had a seizure, consider the following symptoms:

  • Collapsing
  • Jerking
  • Stiffening
  • Loss of consciousness
  • Chomping
  • Muscle twitching
  • Chewing on their tongue
  • Foaming at the mouth or drooling
  • Falling to one side
  • Paddling motions with the legs
  • Defecating or urinating without realizing it

Dog Breeds at Risk of Seizures

Many dog owners may not know that specific breeds are more prone to having seizures. These breeds include:

  • Beagle
  • Shetland Sheepdog
  • Golden Retriever
  • Labrador Retriever
  • Keeshond
  • Belgian Tervuren
  • Vizsla

With that being said, seizures can affect dogs of any and all breeds.

What To Do When A Seizure Occurs

A seizure can be terrifying for a pet parent and disorienting for a dog. With that said, seizures do not cause the dog any pain. However, in order to make the event as controlled and contained as possible, there are a few things you should know.

First, be sure to limit any loud noises or bright lights. Both can cause the seizure to be more severe and cause additional seizures to occur.

Additionally, make sure to remove any other pets from the room. A dog having a seizure can terrify a furry brother or sister and lead to the other dog panicking, barking, or getting involved.

Finally, stay calm. Additional stressors will only lead to the seizure worsening.

Understanding How Phenobarbital Works

Now that we know more about seizures, let’s cover exactly how Phenobarital aims to control them.

A seizure results when there is an abrupt surge in the brain’s neuron activity. Phenobarbital decreases and stabilizes the neuron activity, therefore lessening the severity and frequency of the seizures. Additionally, Phenobarbital also decreases the neurotransmitter, Glutamate, which in turn decreases nerve stimulation in the brain.

Phenobarbital Dosage for Dogs

It is always important that a trained veterinarian determines the appropriate dose of Phenobarbital. The dosage can vary greatly from one dog to the next and will ultimately be based on weight, how frequent the seizures occur, and how severe they are.

We want to mention how important it is to never miss a dose. Doing so can cause your dog to have an incredibly severe seizure episode. Additionally, if you realize that you missed a dose, never give two doses at once. Give them the missed dose as soon as possible and then get back on the regular schedule, typically a dose every 12 hours.

Phenobarbital Side Effects for DogsIncreased Hunger in Dogs from Phenobarbital for Dogs

Now, if you thought the aforementioned information was worrisome, unfortunately, it only gets worse. Here’s where pet parents find themselves in an impossibly difficult predicament: the associated side effects.

Increased Thirst & Excessive Urination

Phenobarbital is known to cause excessive thirst and subsequent excessive urination in epileptic dogs. The side effect will be difficult to overlook as your dog will likely be begging for much more outside time than usual.

Increased Hunger

Additionally, Phenobarbital tends to cause Fido to be much hungrier than usual which can lead to weight gain.

Loss of Coordination

Phenobarbital can trigger ataxia (or loss of coordination) in the dog’s rear limbs. The weakness can come without much warning. Your dog may be moving as they usually do and then quite suddenly become wobbly or fall down.

Lethargy & Depression

A common side effect of Phenobarbital is lethargy which is why it is sometimes used as a sedative.

Depression is also a side effect of the medication and can cause your once active pup to lose interest in activities and sleep the majority of the day.


Conversely, Phenobarbital can cause some dogs to have more energy than they know what to do with. If your dog is being particularly vocal, panting, pacing around the home, or unable to settle down, it’s likely due to the medication.

Vomiting & Weight Loss

Both excessive vomiting and sudden weight loss are symptoms of a dog who experiencing liver damage. If you find that your dog has either one of these symptoms, it is imperative that you see your veterinarian so that they can check liver function and decide whether to proceed with the medication.

Urine Changes

Another telltale sign of liver damage is urine that is very dark in color and strong in odor. Again, if you notice changes in your dog’s urine, call your vet straight away.

Stool Changes

Additionally, changes in stool, such as stool that is gray or mustard in color, is yet another sign of liver failure. Whatever you do, do not delay in getting your dog the medical attention that they need.


Jaundice, or when the whites of the eyes and skin turn yellow in color, is another clear sign that there are problems with liver function. If you notice a yellowing of your dog’s eyes or skin, seek medical intervention immediately.


Finally, although rare, Phenobarbital has caused epileptic dogs to develop anemia. If left untreated, anemia is sure to cause a slew of other issues to occur. It is imperative that you see your vet if for any reason you believe your dog has developed anemia.

Precautions Associated with Phenobarbital

It is extremely important to note that the aforementioned side effects have been found in dogs who otherwise do not have severe health issues. However, there are many dogs who should never be given the drug to begin with as it can cause horrific, irreversible effects, including death. It is extremely important that your vet has a total understanding of your dog’s health condition as well as any other medications that they are currently taking in order to prevent a tragedy from happening.

Dogs with the following health conditions should not take Phenobarbital:

Drug Interactions

Perhaps even more concerning is the amount of medications that have shown to have counteractions with Phenobarbital. These medications include:

  • Anticoagulants
  • Antihistamines
  • Diazepam (along with other central nervous system depressants)
  • Doxycycline
  • Beta-adrenergic blocker
  • Corticosteroids
  • Furosemide
  • Opiate agonists
  • Phenothiazine
  • Aminophylline
  • Chloramphenicol
  • Quinidine
  • Griseofulvin
  • Metronidazole
  • Rifampin
  • Theophylline
  • Valproic acid
  • Phenytoin sodium

Other Epilepsy Medications for Dogs

While Phenobarbital is one of the most commonly prescribed anticonvulsant drugs, it is not the only one that pet owners should be aware of.

Zonisamide for Dogs

If your dog does not react well to Phenobarbital, your veterinarian may prescribe a drug called Zonisamide. The medication can be used on its own or in conjunction with Phenobarbital (as well as Potassium Bromide). With that being said, Zonisamide is also associated with both short-term and long-term side effects including:Avoid Potassium Bromide for Dogs

  • Ataxia
  • Vomiting
  • Diarrhea
  • Loss of appetite
  • Hyperthermia
  • Skin reactions
  • Blood disorders

Diazepam for Dogs

Diazepam is another medication that your veterinarian may prescribe. The drug is typically used to treat seizures and anxiety in pets and people alike. Like all conventional anti-seizure medications, Diazepam has its associated side effects which include:

  • Behavioral changes such as aggression
  • Lethargy and depression
  • Ataxia (loss of coordination)
  • Cardiovascular problems
  • Respiratory issues


Primidone for dogs is yet another anticonvulsant medication that comes with a slew of worrisome adverse reactions including:

  • Weight loss
  • Lethargy
  • Ataxia
  • Hepatic necrosis
  • Fibrosis
  • Cirrhosis of the liver

Keppra or Levetiracetam for Dogs

Levetiracetam for dogs is the generic form of a medication known as Keppra. It is a newer medication that is currently being used to treat epileptic dogs. Many pet parents are excited about Keppra as it can be used in conjunction with Phenobarbital but allow for the dose of Phenobarbital (and associated side effects) to be significantly reduced.

Prescription Anti Seizure Medication: Take Caution

When all is said and done, it’s clear why so many dog owners are actively seeking alternatives for conventional anti-seizure medications. So often it’s hard to say that the pros of the drugs outweigh the potential risks. Of course, you want to free your dog from the harsh realities associated with experiencing seizures, but at what cost? Is it worth the potentially irreversible liver damage? The excessive vomiting? The depression?

Phenobarbital & Potassium Bromide Alternatives

Luckily, there are options that are continuing to prove not only to be effective but also safe for treating epileptic dogs.

CBD for Dogs

One of the forerunners in the world of holistic advancements is none other than CBD. If you are one to stay up on the latest progress in all natural medicine, you’ve likely heard of the incredible herb. Derived from the hemp plant, CBD is proving that holistic alternatives are not only safe, but can be as equally effective as conventional medications.

One of the most highly studied cases of CBD is its effects on people and animals who suffer from seizure disorders and epilepsy. Over three decades of studies prove that CBD effectively decreases seizure frequency and severity not only in people, but our four-legged friends as well.

In fact, CBD has proved to be effective in cases of epileptic patients where conventional medication failed. That’s right. In instances where the dog was resistant to the prescribed anti-seizure drug, CBD worked.

Where Can I Buy CBD Oil

More good news? Because CBD is derived from the hemp plant, it is legal in all 50 states. You can buy CBD oil from the comfort of your couch and within no time see the results for yourself.

In terms of where to buy CBD oil, look no further than Honest Paws. The individuals at Honest Paws believe that our pets deserve the very best, and that’s something we can all wrap our heads around. Their 100% pure full spectrum CBD oil derived from premium-grade hemp plant grown in sunny Colorado. The CBD is non-GMO, soy free, and lab tested which ensures its quality and effectiveness.

CBD Treats

We also love the fact that Honest Paws also has specifically formulated treats that target particular ailments that your pup may be facing. If you have an anxious dog on your hands, try the peanut butter flavored Calming CBD treats. These are particularly important for epileptic dogs as anxiety can cause additional seizures to occur. For dogs suffering from aching bones and joints, Honest Paws offers the Relief Dog Treats and Soft Chews for Joint Support. Allergies getting the best of Fido? Try the Restore CBD Dog Treats.

CBD Tinctures

Finally, for disease prevention as well as treatment for epileptic dogs, CBD oilis exactly what you need. The oil comes in tincture form with an easy-to-use dropper that allows pet parents to have total control over how much of the product their dog receives.

Did we mention that CBD has virtually no adverse effects? That’s right. Zero side effects and a safe, natural way to treat epilepsy in dogs. We highly recommend giving CBD a try!

Diet Matters

In addition to an all natural supplement like CBD, it is important for pet parents to not overlook the importance of diet when it comes to curing and preventing ailments. In fact, a number of studies prove just how powerful a specifically formulated diet can truly be for an epileptic dog. When placed on a strict ketogenic diet, or a diet that is low in carbohydrates and high in fats, both the severity and frequency of the seizure activity significantly reduced.

Furthermore, diet is also particularly important for epileptic dogs who are taking conventional anticonvulsant medications. As we previously mentioned, anti-seizure drugs can cause kidney damage. Diet is a key player when it comes to proving the vital organs with additional support. Many experts recommend a species appropriate raw food diet which ensures that the dog is getting all the necessary nutrients their body needs.

Finally, as always, we encourage our readers to talk to their holistic veterinarian regarding any dietary changes that should be made for their dog’s individual circumstances. All dogs are different but a holistic vet will undoubtedly be able to point you in the right direction.

Acupuncture for Dogs

Lastly, studies show and many pet parents agree that Chinese medicine such as acupuncture has incredibly beneficial results for epileptic dogs. As with most things, acupuncture works best with consistency and we understand that it may not be an appropriate fit for some dog owners. However, it is still comforting to know that there are alternative treatment plans worth exploring.

acupuncture for dogs

Phenobarbital for Dogs: A Final Thought

At the end of the day, nothing would make a dog owner happier than having their beloved pup be seizure free. We can only hope that more and more scientific studies continue to emerge and people continue to be open-minded about the power of holistic medicine. Until the day comes where all dogs can be free of seizures, there is still hope. An epilepsy diagnosis is by no means a death sentence. Epileptic dogs can live full, long, and happy lives. However, it is imperative that pet owners understand their options for treatment and the associated risks involved with nearly every conventional medication. We urge our readers to learn all there is to know about their dog’s condition and, with the help of a trained professional, make a decision about their treatment plan that you feel comfortable with.


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