micrôgam

Also known as microgramme, µg, mcg, micrograms, microg

In the metric system, a microgram or microgramme is a unit of mass equal to one millionth () of a gram. Two different abbreviations are commonly used. The International System of Units (SI) uses μg, where the SI prefix "micro-" is represented by the Greek letter μ (mu). The abbreviation mcg is preferred for medical information in the United States (US), but prescription writing guidance in the United Kingdom advises that "microgram" should not be abbreviated. A third abbreviation, the Greek letter γ (gamma), is no longer recommended. The US Institute for Safe Medication Practices (ISMP) and th