My sister also has type 1 and takes
lantus at bedtime and then takes humalog for correction AND to cover food with carbs, so in her case, if her BG is not High (if it IS under a particular number that she and her doc have discussed), then she does not need a correction shot AND if she was not going to eat anything containing carbs at that time, she would not need humalog to cover food, HOWEVER, she would still take her lantus shot at bedtime.