Alcohol depresses blood sugar (even, I learned, in non-diabetics) and is amplified in many diabetes medications. But the effect can be delayed several hours, so blood sugar not long after a meal with booze can be on the high side, then crash in hypoglycemia. This has happened to me, so now I prepare for it whenever I have booze with dinner: check sugars immediately before bed, have a little something extra if the reading is on the low side of normal.

So yes, correct information on the last meal—and what was in the last meal — is important.