TABLE 2.
Geometric mean (95% confidence interval) of AUC2‐4 and partial metabolic clearance of midazolam after oral administration of 30 μg oral midazolam at baseline, at 300, 900, and 1800 mg St. John's wort, and at 1800 mg St. John's wort plus 600 mg rifampin in 11 healthy volunteers.
| Treatment | Duration (days) | AUC2‐4 (h pg mL−1) | eCLmet (mL min−1) | GMR (90% CI) of eCLmet |
|---|---|---|---|---|
| Baseline | – | 65.7 (51.2–84.3) | 843 (657–1081) | – |
| 300 mg/day St. John's wort | 14 | 33.6* (26.3–42.8) | 1649* (1290–2104) | 1.957 (1.661–2.305) |
| 900 mg/day St. John's wort | 14 | 17.0*,# (13.9–20.9) | 3257*,# (2653–3999) | 3.864 (3.393–4.400) |
| 1800 mg/day St. John's wort | 14 | 11.7*,# (9.14–15.0) | 4739*,# (3705–6061) | 5.621 (4.815–6.562) |
| 1800 mg/day St. John's wort + 600 mg/day rifampin | 7 | 3.76*,# (3.00–4.71) | 14,752*,# (11,766–18,495) | 17.50 (15.41–19.87) |
Note: Test versus baseline: *p < 0.001; Test versus next lower St. John's Wort dose: # p < 0.001.
Abbreviations: AUC2‐4, area under the concentration–time curve from 2 to 4 h; CI, confidence interval; eCLmet, estimated midazolam partial metabolic clearance; GMR, geometric mean ratio.