When administering medication, which abbreviation indicates a quantity of one?

The abbreviation that indicates a quantity of one is "I" or "i." In medical terminology, the letter "I" is derived from the Roman numeral system, where "I" represents the number one. This understanding is important in the context of medication administration, as accurate dosage is crucial for patient safety and efficacy of treatment.

The other abbreviations represent different quantities or concepts in medication administration. "ss" typically stands for "half," indicating a quantity of one-half (0.5), while "II" or "ii" indicates two. The abbreviation "dr" is often used to refer to a dram, which is a unit of measurement for volume but does not indicate a specific quantity of one. Therefore, recognizing and understanding these abbreviations helps ensure precise communication in healthcare settings.