Table 5

Noncompartmental pharmacokinetic parameters for14C-equivalents, atomoxetine, and its metabolites in CYP2D6 poor metabolizer subjects following oral administration of14C-atomoxetine5-a

ParameterArithmetic Mean (CV%)
14C-Equivalents5-bAtomoxetine4-HydroxyatomoxetineN-Desmethylatomoxetine4-Hydroxyatomoxetine-O-glucuronide
C ss,max(ng/ml)427.75 (30.5)914.72 (30.5)259.22 (39.6)88.00 (16.9)
C ss,min(ng/ml)502.84 (29.2)193.09 (40.6)69.27 (16.4)
C ss,avg(ng/ml)703.63 (26.9)234.89 (41.2)77.88 (17.0)
T max 5-c(h)2.00 (2.00–6.00)2.00 (2.00–3.00)6.00 (3.00–6.00)4.00 (2.00–6.00)
t 1/2 5-d(h)62.4 (61.9–63.3)20.0 (16.8–25.2)33.3 (27.7–42.7)19.0 (15.2–22.8)
AUC0–τ(μg · h/ml)18.4 (13.5)8.44 (26.9)2.82 (41.2)0.935 (17.0)
CLss/F(l/h/kg)0.0157 (22.6)0.0357 (26.2)
V z/F(l/kg)1.41 (22.6)1.06 (42.9)
  • 5-a  Multiple 20-mg doses of atomoxetine were administered twice daily over 5 days followed by a single radiolabeled atomoxetine 20-mg dose (actual dose 19.66 mg; 92.4 μCi) on the morning of the 6th day.

  • 5-b  Single dose parameters are reported for 14C-equivalents: Cmax,Tmax, t1/2, AUC0–∞, CL/F, Vz/F.

  • 5-c  Median (range).

  • 5-d  Mean (range).