What is the correct abbreviation for a milligram?

The abbreviation for a milligram is "mg." This abbreviation is widely recognized and used in medical and pharmaceutical contexts to denote a unit of mass equal to one-thousandth of a gram. Understanding this abbreviation is crucial for accurate medication dosing and communication in healthcare settings, as milligrams are commonly used to specify the dosage of various medications.

"mcg" stands for microgram, which is one-millionth of a gram and a different measurement unit altogether. "gtt" refers to drop, which is used in the context of fluid measurements but is not related to mass. "gm," while sometimes seen as a shorthand for gram, is less commonly used than "g" and can lead to confusion since it may imply a different measurement if misinterpreted. Therefore, "mg" is the standard and correct abbreviation for milligram in medication practice.