Comparison of phenobarbital with bromide as a first-choice antiepileptic drug for treatment of epilepsy in dogs.

Abstract

OBJECTIVE:

To compare efficacy and safety of treatment with phenobarbital or bromide as the first-choice antiepileptic drug (AED) in dogs.

DESIGN:

Double-blinded, randomized, parallel, clinical trial.

ANIMALS:

46 AED-naïve dogs with naturally occurring epilepsy.

PROCEDURES:

Study inclusion was based on age, history, findings on physical and neurologic examinations, and clinicopathologic test results. For either phenobarbital treatment (21 dogs) or bromide treatment (25), a 7-day loading dose period was initiated along with a maintenance dose, which was adjusted on the basis of monthly monitoring. Efficacy and safety outcomes were compared between times (baseline and study end [generally 6 months]) and between drugs.

RESULTS:

Phenobarbital treatment resulted in eradication of seizures (17/20 [85%]) significantly more often than did bromide (12/23 [52%]); phenobarbital treatment also resulted in a greater percentage decrease in seizure duration (88 ± 34%), compared with bromide (49 ± 75%). Seizure activity worsened in 3 bromide-treated dogs only. In dogs with seizure eradication, mean ± SD serum phenobarbital concentration was 25 ± 6 μg/mL (phenobarbital dosage, 4.1 ± 1.1 mg/kg [1.9 ± 0.5 mg/lb], p.o., q 12 h) and mean serum bromide concentration was 1.8 ± 0.6 mg/mL (bromide dosage, 31 ± 11 mg/kg [14 ± 5 mg/lb], p.o., q 12 h). Ataxia, lethargy, and polydipsia were greater at 1 month for phenobarbital-treated dogs; vomiting was greater for bromide-treated dogs at 1 month and study end.

CONCLUSIONS AND CLINICAL RELEVANCE:

Both phenobarbital and bromide were reasonable first-choice AEDs for dogs, but phenobarbital was more effective and better tolerated during the first 6 months of treatment.

• Authors: Dawn Merton Boothe, Curtis Dewey, David Mark Carpenter
• Journal: Journal of the American Veterinary Medical Association (J Am Vet Med Assoc) Vol. 240 Issue 9 Pg. 1073-83 (May 01 2012) ISSN: 1943-569X [Electronic] United States
• PMID: 22515627 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anticonvulsants
• Bromides
• Phenobarbital

Topics

• Animals
• Anticonvulsants (therapeutic use)
• Bromides (therapeutic use)
• Dog Diseases (drug therapy)
• Dogs
• Epilepsy (drug therapy, veterinary)
• Female
• Male
• Phenobarbital (therapeutic use)
• Time Factors
• Treatment Outcome