Hi John. Cetrine is a brand name version of the common antihistamine cetirizine.
This medication is safe to take with Keppra at usual doses. No adverse side effects would be expected.
Hi John. There are a lot of medications that contain this warning. Manufacturers often include it to cover themselves in the very unlikely event of a seizure. While it is always a possibility, I have never seen this medication trigger a seizure. Keep in mind that alcohol can also be dangerous in those predisposed to seizures. And drinking too much water can also trigger a seizure.
Did his seizures occur within 36 hours of taking the cetrine (while it was in his bloodstream)? Has there been any seizure activity off the cetrine?