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Mixing & materials
Units: IU, mg, mcg
·independent & ad-free
Units: IU, mg, mcg - mg (milligram) and mcg/µg (microgram) are masses; 1 mg = 1000 mcg. IU (international unit) measures effect, not mass - the two must not be equated.
Also called IUmgmcgµgmicrogrammilligraminternational unit
Three units come up constantly - and they measure different things:
- mg (milligram) and mcg/µg (microgram) are masses. Note 1 mg = 1000 mcg.
- IU (international unit) measures a substance's biological effect, not its mass. How many mg an IU corresponds to differs from substance to substance.
Why this constantly causes errors
The most common mistake is confusing mcg and mg (a factor of 1000) or equating IU with mg. On top of that, the insulin-syringe „unit" is a volume on the scale - a third meaning of „unit".
Rule of thumb
Mass (mg/mcg) is fixed; IU is effect-based; the syringe unit is volume. When calculating, always be clear which „unit" you mean.