Table 4

Noncompartmental pharmacokinetic parameters for14C-equivalents, atomoxetine, and its metabolites in CYP2D6 extensive metabolizer subjects following oral administration of14C-atomoxetine4-a

ParameterArithmetic Mean (CV %)
14C-Equivalents4-bAtomoxetine4-HydroxyatomoxetineN-Desmethylatomoxetine4-Hydroxyatomoxetine-O-Glucuronide
C ss,max(ng/ml)515.42 (22.9)159.70 (51.9)2.03 (17.5)7.02 (71.5)413.88 (35.5)
C ss,min(ng/ml)36.05 (115.8)0.52 (115.6)3.12 (113.6)104.36 (19.3)
C ss,avg(ng/ml)89.64 (64.3)5.15 (86.4)228.70 (13.6)
T max 4-c(h)2.00 (2.00–4.00)2.00 (1.00–3.00)2.50 (2.00–4.00)3.50 (2.00–6.00)2.00 (2.00–4.00)
t 1/2 4-d(h)17.7 (15.1–19.3)5.34 (3.67–9.09)8.97 (2.11–21.9)6.74 (5.90–8.30)
AUC0–τ(μg · h/ml)4.54 (16.8)1.08 (64.3)0.0618 (86.4)2.74 (13.6)
CLss/F(l/h/kg)0.0605 (26.2)0.373 (75.1)
V z/F(l/kg)1.56 (32.7)2.33 (51.0)
  • 4-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.

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

  • 4-c  Median (range).

  • 4-d  Mean (range).