Doses - FOMEPIZOLE, 4-METHYLPYRAZOLE
Dogs: 
For treatment of ethylene glycol toxicity: a) Initially load at 20 mg/kg IV; at 12 hours post initial dose give 15 mg/kg IV; at 24 hours post initial dose give another 15 mg/kg IV and at 36 hours after initial dose give 5 mg/kg; may give additional 5 mg/kg doses as necessary (animal has not recovered or has additional ethylene glycol in blood). (Package Insert ¯ Antizol-Vet® )
Monitoring Parameters - 1) Ethylene glycol blood levels (mostly important to document diagnosis if necessary and to determine if therapy can be discontinued after 36 hours of Tx.) 2) Blood gases and serum electrolytes 3) Hydration status 4) Renal function tests (e.g., Urine output and urinalysis; BUN or serum creatinine)
Client Information - Clients should be informed that treatment of serious ethylene glycol toxicity is an "intensive care" admission and that appropriate monitoring and therapy can be quite expensive, particularly when fomepizole is used in large dogs. Because time is of the essence in thistherapy, clients will need to make an informed decision rapidly. Dogs treated within 8 hours postingestion have a significantly better prognosis than those treated after 10-12 hours post ingestion.
Dosage Forms/Preparations/FDA Approval Status - Veterinary-Approved Products:
Fomepizole 1.5 g Kit for Injection; Antizol-Vet® (Orphan Medical); (Rx) Approved for use indogs.
Preparation: If drug has solidified run warm water over vial; Add entire contents to 30 ml vial of0.9% NaCl (in kit), mix well. Resultant solution is: 50 mg/ml
Note: At recommended doses 1 kit will treat a 26 kg dog (up to 58 lb.); larger dogs will requireadditional kits