What does "b.i.d." stand for in medication dosage?

The abbreviation "b.i.d." stands for "bis in die," which is Latin for "twice a day." This dosing schedule indicates that a medication should be administered two times within a 24-hour period. For example, if a medication is prescribed to be taken b.i.d., it would typically be taken in the morning and again in the evening, ensuring that the medication maintains an effective level in the body throughout the day.

In contrast, the other options represent different dosing requirements. "Before meals" indicates when to take a medication relative to food intake, "every hour" suggests a much more frequent dosing schedule, and "once a day" means the medication is taken only one time in a 24-hour period. Each of these alternatives has a distinct frequency and timing that does not match the definition of b.i.d.