dibucaine number

Also found in: Acronyms.

di·bu·caine num·ber (DN),

(dib'yū-kān nŭm'bĕr),
A test for differentiation of one of several forms of atypical pseudocholinesterases that are unable to inactivate succinylcholine at normal rates; based on the percentage of inhibition of the enzymes by dibucaine, normal enzyme has a DN of at least 75 and higher, heterozygous atypical enzyme has a DN of 40-70, and homozygous atypical enzyme has a DN of less than 20.
See also: fluoride number.