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a test performed at Texas A&M University which will measure EG and metabolites from serum, stomach contents or urine.  The problem with the test is that the animal will be dead by the time the results return.  Kidney biopsy can also result in a definitive diagnosis. 

Treatment:
The goal of treatment, is to competitively inhibit the enzyme alcohol dehydrogenase from metabolizing EG.  Alcohol dehydrogenase must be tied up long enough for the body to eliminate EG in an unmetabolized form.

Fomepizole which is another name for 4-MP or Antizol VETâ is a drug that will inhibit alcohol dehydrogenase from metabolizing EG (Fig 4).  The drug comes in a vial and needs to be reconstituted with 0.9% sodium chloride.  When reconstituted, it makes a 50 mg/ml solution.  The following is a treatment schedule for dogs:
1. Load with a dose of 20 mg/kg
2. 12 hours after intitial dose, administer 15 mg/kg
3. 24 hours after initial dose, administer 15 mg/kg
4. 36 hours hours after initial dose, administer 5 mg/kg

Fomepizole is only approved for use in dogs.  There have been studies to determine efficacy of use in cats, however those studies have shown that fomepizole was only effective if given to cats immediately (time 0) following ingestion of EG.    The best treatment for EG toxicity in cats, is ethanol therapy.

An alternative to using fomepizole, is to administer ethanol.  Ethanol can be used in dogs and cats as an ADH inhibitor.   The downfall, is that it causes CNS depression, making patient monitoring difficult.  Ethanol should not be administered if the patient presents at 18 hours or more after clinical signs have started, because all of the EG has been metabolized at that point.

The recommended treatment protocol for ethanol is as follows:
Dogs:
1. 5.5 mls of 20% ethanol/ kg of body weight administered IV at 4 hour intervals for 5 treatments.
2. Then 5.5 mls of 20% ethanol/ kg of body weight administered IV at 6 hours intervals for 4 treatments.
Cats:
1. 5 mls of 20% ethanol/ kg of body weight given intraperitoneally every 6 hours for 5 treatments
2. 5 mls of 20% ethanol/ kg of body weight given intraperitoneally every 8 hours for 4 treatments.

In addition to administering  an ADH competitive inhibitor, the following should be implemented in your treatment protocol:
1.  Administer activated charcoal if within 1 to 2 hours after ingestion.
2.  IV fluid diuresis
3. Administer sodium bicarbonate based on blood gas results
· Dogs (0.3 x body wt. (kg) x (21 - patient HCO3-)
· Cats (0.3 x body wt. (kg) x (19 - patient HC03- )