Table 3.

Estimated Maternal Steady-State Atenolol Plasma Pharmacokinetic Parameters (mean ± SD) 2–4 Weeks, 3–4 Months and 6–8 Months Postpartum

Parameter	2–4 Weeks Postpartum	3–4 Months Postpartum	6–8 Months Postpartum
Apparent Oral Clearance (L/hr)	22.1 ± 5.5	26.7 ± 11.2	26.6 ± 12.2
Renal Clearance (mL/min)	171 ± 42	167 ± 51	176 ± 47
AUC (ng•hr/mL)	1261 ± 715‡	1017 ± 955	888 ± 415
Dose Normalized AUC (ng •hr/mL at 50 mg/day)	1201 ± 300	1099 ± 452	1118 ± 431
Cmax (ng/mL)	192 ± 124	164 ± 155	144 ± 67
Dose Normalized Cmax (ng/mL at 50 mg/day)	182 ± 58	175 ± 71	182 ± 74
Tmax (hr)	2.4 ± 0.8	1.8 ± 1.0	2.0 ± 0.7
Half Life (hr)	6.2 ± 2.2	6.4 ± 1.4	6.5 ± 2.4
Apparent Volume of Distribution (L)	198 ± 81	249 ± 126	248 ± 151
Fraction Excreted Unchanged in the Urine (%)	47.7 ± 11.0	41.2 ± 13.7	44.2 ± 14.6
Creatinine Clearance (mL/min)	133 ± 23‡	139 ± 41‡	159 ± 48

Only subjects completing all 3 study days (n = 17) are included. Atenolol dose ranged from 25–100 mg/day. AUC = area under the concentration-time curve; Cmax = maximum concentration; Tmax = time to maximum concentration.

^‡, P < 0.01.