Which of the following is NOT a common abbreviation used in medication instructions?

The abbreviation "med." is not commonly recognized as a standardized abbreviation for medication instructions. In pharmaceutical terminology, "med." may refer to "medication" in a general sense, but it does not convey specific dosing instructions or directions for administration like the other abbreviations listed.

On the other hand, "q.d." stands for “quaque die” which means once a day, providing specific dosing frequency. "Stat" indicates that a medication should be administered immediately, reflecting urgency in a clinical setting. "Ung" is short for "unguent," which refers to ointments. These abbreviations are widely accepted in medical practice and known by healthcare professionals for their specific meanings in prescriptions and medication orders.

Choosing "med." as not being a commonly used abbreviation highlights the importance of understanding specific medical terminologies and their applications in medication administration.