Table 3.
Pharmacokinetic parameters for sildenafil and N‐desmethyl sildenafil after either F1 or F2 administration
| Analyte | Sildenafil | N‐desmethyl sildenafil | |||
|---|---|---|---|---|---|
| formulation | F1 | F2 | F1 | F2 | |
| n | 12 | 12 | 12 | 12 | |
| C max (ng ml –1 ) | Mean | 268 | 173 | 55.5 | 42.7 |
| 95% CI | 188, 348 | 126, 220 | 44.1, 66.9 | 32.3, 53.1 | |
| Ratio† | 0.67 | 0.74 | |||
| 90% CI | 0.43, 1.05 | 0.53, 1.04 | |||
| AUC(0,1590 min) (ng ml –1 h) | Mean | 577 | 476 | 194 | 155 |
| 95% CI | 462, 692 | 401, 551 | 143, 245 | 127, 183 | |
| Ratio† | 0.84 | 0.85 | |||
| 90% CI | 0.71, 0.99 | 0.75, 0.96 | |||
| AUC(0,∞) (ng ml –1 h) | Mean | 596 | 500 | 203 | 171 |
| 95% CI | 481, 711 | 423, 577 | 151, 255 | 139, 203 | |
| t max (h) | Mean | 3.88 | 3.10 | 4.00 | 3.34 |
| 95% CI | 3.27, 4.49 | 2.74, 3.46 | 3.28, 4.72 | 2.89, 3.79 | |
| t lag (h) | Mean | 3.00 | 2.75 | 3.29 | 2.78 |
| 95% CI | 2.72, 3.28 | 2.40, 3.10 | 2.94, 3.64 | 2.37, 3.19 | |
| t 1/2 (h) | Mean | 3.87 | 4.96 | 5.21 | 7.07* |
| 95% CI | 2.72, 5.02 | 3.82, 6.10 | 4.55, 5.87 | 5.79, 8.35 | |
*
P < 0.05, value at F2 is significantly different from F1.
†
Ratio of geometric least square means. AUC(0,1590 min), area under the curve from time 0 to 1590 min; AUC(0,∞), area under the curve from time 0 to infinity; C max, maximum concentration; t lag, time to first measurable quantity; t max, time to maximum concentration; t ½, half‐life.