| |
After a single oral dose of 0.4 mg FLOMAX CR in the fasted state, the plasma concentration of tamsulosin gradually increased reaching Cmax at a median time of 6 hours. At steady state, which is reached by day 4 of multiple dosing, plasma concentrations of tamsulosin peak at 4-6 hours in the fasted and fed state. Peak plasma concentrations increase from approximately 6 ng/mL after the first dose to 11 ng/mL in steady state. After Cmax is reached, the plasma concentration decreases, but at approximately 16-24 hours post-dose, a small increase or second plateau is observed. The absolute bioavailability of tamsulosin from FLOMAX CR was estimated to be 55-59%.
A study conducted at steady state with 0.4 mg FLOMAX CR demonstrated that the plasma concentration-time profile in the fed state was bioequivalent to the fasted state, indicating the absence of a food effect ( Table 1).
Table 1: FLOMAX CR
Mean Pharmacokinetic Parameters of Tamsulosin at Steady Stage Following Administration of Once Daily Doses of 0.4 mg FLOMAX CR in Both the Fed and Fasted State
| Parameter |
Flomax CR 0.4 mg (Fed)
(n=24)
|
Flomax CR 0.4 mg (Fasted)
(n=24)
|
| AUC0-inf (ng.h/mL) |
291.1 |
278.7 |
| Cmax (ng/mL) |
11.1 |
10.7 |
| C24 (ng/ml) |
4.8 |
4.6 |
| Tmax (h) |
4.16 |
4.75 |
| T1/2 (h) |
14.6 |
15.6 |
|
