international unit(redirected from I.U)
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n. Abbr. IU
1. The quantity of a biologically active substance, such as a hormone or vitamin, required to produce a specific response.
2. A unit of potency for similarly active substances, based on this quantity and accepted as an international standard.
1. an internationally accepted standard, derived by bioassay, to which samples of a pharmaceutical substance are compared for ascertaining their relative potency.
2. the specific biologically effective quantity of such a substance.Abbr.: IU
A unit for measuring a biologically active substance, such as a hormone or vitamin.
n. unidad internacional, medida de una sustancia definida aceptada por la Conferencia Internacional de Unificación de Fórmulas.