Mean (±S.E.M.) plasma levels (micrograms per milliliter) of parent drugs and their metabolites 2 h after the last of 10 consecutive daily i.p. injections of different doses of heroin or morphine
Heroin | 6-MAM | Morphine | M3G | M6G | |
|---|---|---|---|---|---|
| Repeated heroin | |||||
| 2.5 mg/kg × 10 | 1.2 ± 0.1 | 1.4 ± 0.3 | 0.5 ± 0.2 | 0.5 ± 0.1 | 0.06 ± 0.05 |
| 5.0 mg/kg × 10 | 1.3 ± 0.02 | 1.8 ± 0.1 | 0.6 ± 0.1 | 0.8 ± 0.1 | 0.08 ± 0.08 |
| 10 mg/kg × 10 | 1.8 ± 0.05 | 2.4 ± 0.3 | 1.2 ± 0.2 | 0.6 ± 0.1 | 0.07 ± 0.06 |
| Repeated morphine | |||||
| 10 mg/kg × 10 | n.d. | n.d. | 2.5 ± 0.5 | 1.3 ± 0.2 | n.d. |
| 20 mg/kg × 10 | n.d. | n.d. | 2.4 ± 0.1 | 1.3 ± 0.03 | n.d. |
| 40 mg/kg × 10 | n.d. | n.d. | 2.8 ± 0.4 | 1.7 ± 0.1 | n.d. |
n.d., not detectable.