well he was down to 34 one night. which i was told is ok. he cant go hypo with no insulin. i was told some meters just read low when the bg numbers are back to normal, and he had not eaten for a while, so it could of also been like that because it was a fasting number. i was also told the a lot of "normal" cats that have never had diabetes can have a bg in the 50ies and that is normal. i too was a little freaked out by the low numbers, but he seems fine.