Table 2

Enzyme kinetic parameters for terbinafine metabolism

PathwaysHuman LiversKmVmaxCIint
μM nmol/h/mg protein ml/h/mg protein
AllGGM00222.6243.810.8
HL-44A18.2128.37.1
HL-46A19.6172.08.8
mean ± S.D.20.1 ± 2.2181.4 ± 58.38.9 ± 1.9
Side-chain oxidationGGM00212.819.91.6
OL+CA+DOLHL-44A5.916.82.8
HL-46A14.99.70.7
mean ± S.D.11.2 ± 4.715.5 ± 5.21.7 ± 1.1
N-DemethylationGGM00217.072.44.3
D+DOL+D-DHDsHL-44A12.132.62.7
HL-46A16.751.03.1
mean ± S.D.15.3 ± 2.752.0 ± 19.93.4 ± 0.8
DeaminationGGM00224.696.13.9
NAL+NM+NAHL-44A33.260.11.8
HL-46A25.689.83.5
mean ± S.D.27.8 ± 4.782.0 ± 19.23.1 ± 1.1
Dihydrodiol formationGGM0023.613.83.9
DHDs+D-DHDsHL-44A5.88.61.5
HL-46A3.86.91.8
mean ± S.D.4.4 ± 1.29.8 ± 3.62.4 ± 1.3

[14C]Terbinafine (2–220 μM) metabolite formation was investigated by three different human liver microsomal preparations.