Microgram
| Microgram | |
|---|---|
 Anutrition facts labeldisplaying, for example, the amount offolic acidin micrograms | |
| General information | |
| Unit system | SI |
| Unit of | mass |
| Symbol | μg |
In themetric system,amicrogramormicrogrammeis aunitofmassequal to one millionth (1×10−6) of agram.The unit symbol isμgaccording to theInternational System of Units(SI); the recommended symbol in the United States and United Kingdom when communicating medical information ismcg.In μg, the prefix symbol formicro-is the Greek letterμ (mu).
Abbreviation and symbol confusion
[edit]When the Greek lowercase "μ" (mu) is typographically unavailable, it is occasionally – although not properly – replaced by the Latin lowercase "u".
The United States-basedInstitute for Safe Medication Practices(ISMP) and the U.S.Food and Drug Administration(FDA) recommend that the symbol μg should not be used when communicating medical information due to the risk that the prefixμ (micro-)might be misread as the prefixm (milli-),resulting in a thousandfold overdose. The ISMP recommends the non-SIsymbolmcginstead.[1]However, the abbreviation mcg is also the symbol for an obsoletecentimetre–gram–second system of unitsunit of measure known as millicentigram, which is equal to 10 μg.
Gamma (symbol:γ) is a deprecated non-SI unit ofmassequal to 1 μg.[2]
Afullwidthversion of the "microgram" symbol is encoded byUnicodeat code pointU+338D㎍SQUARE MU Gfor use inCJKcontexts.[3]In other contexts, a sequence of the Greek lettermu(U+03BC) and Latin letter g (U+0067) should be used.
See also
[edit]
- List of SI prefixes
- Orders of magnitude (mass),listing a few items that have a mass of around 1 μg.
References
[edit]- ^"ISMP's List of Error-Prone Abbreviations, Symbols, and Dose Designations".ISMP.Retrieved2018-03-28.
- ^NIST Handbook 133 - 2018,Appendix E. General Tables of Units of Measurement, page 159 (17)
- ^Unicode Consortium(2019)."The Unicode Standard 12.0 – CJK Compatibility ❰ Range: 3300—33FF ❱"(PDF).Unicode.org.RetrievedMay 24,2019.