What dog food did you switch to? Was it a fast change or gradually over a week or so?
The dosage of the phenobarb (1mg/lb q12h) and metronidazole (10mg/lb q12h) is within the usual dosages given initially, however any animal can have variable response to any medication, either overly sensitive like your dog or under responsive. The combination with the metronidazole may have amplified the effect if he was prone to sensitivity, altho metronidazole is not known to potentiate the effects of the phenobarb. The phenobarb can actually decrease the effectiveness of the metronidazole. I asked about bloodwork because poor liver function may decrease the clearance of the phenobarb and metronidazole, but if everything checked out OK, this probably isn't the issue.
Sleeping it off under your supervision may be the only thing that can be done along with offering him water. If he won't drink he may need more IV fluids. I would have his bloodwork checked again this week sometime just to be sure things are still OK.
Did he have multiple seizures before starting medication? If not, it may be an option to withhold medication to see if he ever has another seizure (some dogs have one and never have another one again).
Edited by harmonyvet on January 7 2006 at 2:30 PM
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