mcg

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Microgram

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mcg

1. (medicine) (metrology) Symbol for microgram, an SI unit of mass equal to 10⁻⁶ grams.

This abbreviation is used in the medical field instead of the standard abbreviation μg to avoid the chance that in handwritten dosing instructions it would be misread as mg (“milligram”) resulting 1000 times the intended dose.

• µg
• ug