From the Guidelines
Common anti-seizure medications for dogs include phenobarbital, potassium bromide, levetiracetam (Keppra), zonisamide, and diazepam, with phenobarbital typically being the first-choice medication. The choice of medication depends on various factors, including the type and severity of seizures, as well as the individual dog's response to treatment.
Key Medications
- Phenobarbital is usually administered at 2-4 mg/kg twice daily, with blood levels monitored regularly to ensure proper dosing 1.
- Potassium bromide (30-40 mg/kg once daily) is often used as an alternative or in combination with phenobarbital for dogs with difficult-to-control seizures.
- Levetiracetam (20 mg/kg three times daily) is valued for its minimal side effects and can be used for emergency seizure management, as supported by a study on its efficacy in managing status epilepticus 1.
- Zonisamide (5-10 mg/kg twice daily) is useful for dogs that don't respond well to other medications.
- Diazepam is primarily used for emergency treatment of active seizures rather than long-term management.
Treatment Considerations
These medications work by different mechanisms to stabilize electrical activity in the brain, preventing the abnormal firing patterns that cause seizures. Treatment is typically lifelong, and medication should never be stopped abruptly as this can trigger severe seizures. Regular veterinary monitoring is essential to check drug levels, liver function, and adjust dosages as needed. Side effects vary by medication but can include sedation, increased thirst and appetite, liver issues, and coordination problems.
Recent Guidelines
A recent clinical policy approved by the ACEP board of directors in 2024 emphasizes the importance of early treatment and cessation of status epilepticus to reduce morbidity and mortality, highlighting the benefits of medications like levetiracetam, fosphenytoin, or valproate in achieving this goal 1.
From the Research
Common Anti-Seizure Medications for Dogs
- Oral phenobarbital and imepitoin are likely to be effective for the treatment of idiopathic epilepsy (IE) in dogs, with a good level of evidence supporting their efficacy 2
- Potassium bromide and levetiracetam also have a fair level of evidence supporting their efficacy for the treatment of IE in dogs 2
- Levetiracetam is a broad-spectrum antiepileptic drug that is effective against a variety of seizure types, with a favorable pharmacokinetic profile and minimal drug-drug interactions 3, 4
- The efficacy and safety of levetiracetam have been established in numerous randomized, double-blind, controlled, multicentre trials in patients with epilepsy, including those with refractory partial onset seizures and idiopathic generalized epilepsy 4
Treatment Strategies
- The goal of seizure management in dogs is to establish a predetermined, concise, and logical sequential approach to chronic seizure management, starting with seizure identification and diagnosis 5
- Treatment strategies may involve the use of antiepileptic drugs, such as phenobarbital, imepitoin, potassium bromide, and levetiracetam, as well as other therapies to enhance patient response and quality of life 5
- The choice of antiepileptic drug and treatment strategy will depend on the individual dog's needs and medical history, as well as the severity and frequency of seizures 2, 5
Efficacy and Safety
- Levetiracetam has been shown to be effective and safe for the treatment of neonatal seizures, with a lower incidence of side effects compared to phenobarbital 6
- The incidence of hypotension and respiratory depression was significantly lower in dogs treated with levetiracetam compared to those treated with phenobarbital 6
- Levetiracetam is generally well tolerated, with most treatment-emergent adverse events being mild to moderate in severity 4