Suspected phenobarbital-induced fever in a cat.

Area of Science:

• Veterinary Neurology
• Clinical Pharmacology
• Feline Medicine

Background:

• Anticonvulsant medications are crucial for managing seizures in veterinary patients.
• Drug-induced fever is a recognized adverse effect in human medicine, but less documented in veterinary literature.
• Phenobarbital is a commonly prescribed anticonvulsant for feline epilepsy.

Observation:

• A 3-year-old domestic shorthair cat presented with fever following initiation of phenobarbital therapy.
• Comprehensive diagnostic work-up, including advanced imaging and infectious disease testing, did not reveal an underlying cause for the fever.
• The cat's fever resolved within 24 hours after discontinuing phenobarbital and initiating pregabalin.

Findings:

• This case suggests phenobarbital can induce fever in cats as an isolated adverse effect.
• The fever's rapid resolution upon drug withdrawal strongly supports a phenobarbital-induced etiology.
• This presentation is distinct from previously documented hypersensitivity reactions to anticonvulsants in veterinary medicine.

Implications:

• Veterinarians should consider drug-induced fever in cats presenting with unexplained fever after starting phenobarbital.
• Phenobarbital-induced fever should be included in the differential diagnosis for fever of unknown origin in cats.
• This case highlights the importance of pharmacovigilance for anticonvulsant drugs in veterinary practice.