Table 1.
Effect of grapefruit juice coadministration on the pharmacokinetics of amlodipine.
| Pharmacokinetic variable for amlodipine | Amlodipine + grapefruit juice | Amlodipine + water (control) | Ratio juice/water Point estimate (%) and 95% CI |
|---|---|---|---|
| Oral amlodipine | |||
| Cmax (ng ml−1) | 6.2 ± 1.1 | 5.8 ± 1.1 | 107.1 (91.7, 125.0) |
| AUC(0,∞) (ng ml−1 h) | 315 ± 76 | 293 ± 58 | 107.8 (99.7, 116.5) |
| tmax (h after dose) | 7.6 ± 1.4 | 7.9 ± 1.7 | 0.2 (−0.9, 0.5) |
| kel (h−1) | 0.0166 ± 0.0034 | 0.0177 ± 0.0034 | −0.0010 (–0.0026, 0.0007) |
| F | 0.88 ± 0.15 | 0.81 ± 0.14 | 107.9 (98.4, 118.4) |
| Intravenous amlodipine | |||
| Cmax (ng ml−1) | 30.1 ± 12.1 | 34.8 ± 13.7 | 85.9 (73.6, 100.3) |
| AUC(0,∞) (ng ml−1 h) | 374 ± 88 | 358 ± 88 | 102.5 (94.8, 110.9) |
| kel (h−1) | 0.0161 ± 0.0029 | 0.0181 ± 0.0041 | −0.0022 (–0.0039, −0.0005)⋆ |
| CL (ml min−1 kg−1) | 6.65 ± 1.99 | 6.93 ± 1.72 | –0.2 (–1.1, 0.8) |
| Vdss (l kg−1) | 22.7 ± 5.1 | 21.0 ± 3.8 | 1.9 (–0.7, 4.5) |
Mean ± s.d. values. Point estimates (and 95% CI) are either the ratio of the adjusted geometric means of treatments (Cmax, AUC), arithmetic means (F), or the difference in the adjusted arithmetic means of treatment (all other kinetic variables).
⋆
P < 0.05.