Phenobarbital for Seizures in Labradors

Phenobarbital is a barbiturate drug commonly prescribed to epileptic dogs. It is a safe medication, but there are side effects and drug interactions to take into account, and the dosing schedule must be strictly adhered to if seizures are to be prevented.

  1. Frequent Testing

    • Mar Vista Animal Medical Center recommends twice-yearly blood tests to ensure that the phenobarbital levels in the blood are acceptable. This periodic monitoring prevents the occurrence of liver and kidney damage associated with long-term use of the drug.

    Drug Interactions

    • Phenobarbital can reduce the effectiveness of certain medications, including corticosteroids, some antibiotics, drugs for Cushing’s disease and heart medications. Any medication with sedation properties, including antihistamines, can increase the effect of phenobarbital. Make sure your vet knows about all medication your dog is taking.

    Dosing Schedule

    • Seizures can result if even one phenobarbital dose is skipped, so be absolutely certain to stick to the prescribed dosing schedule. If you think you may not be able to, speak with your vet about possible alternatives.

    Side Effects

    • The most common side effect is increased thirst and urination, which will continue as long as the dog is on the medication. Some dogs may be drowsy or lethargic at the beginning of treatment, but this goes away as their bodies gradually adjust to the drug. If drowsiness continues, the phenobarbital dose may need to be changed.

    Unintended Benefit

    • Labradors are prone to exercise-induced collapse, in which their legs become too weak to support their weight after five to 20 minutes of strenuous activity. Phenobarbital reduces the excitability of the brain cells and discourages abnormal electrical impulses, thereby making it an effective treatment for collapse. It is thought that labs taking phenobarbital long-term may be at a reduced risk for this condition.