Jarvis M A, Wu-Pong S, Kniseley J S, Schnoll S H
Department of Psychiatry, Medical College of Virginia Campus of Virginia Commonwealth University, Richmond 23298, USA.
J Addict Dis. 1999;18(4):51-61. doi: 10.1300/J069v18n04_05.
Traditionally, methadone maintenance therapy has been a once-daily dosing schedule. The current study evaluates the effectiveness of this regimen during pregnancy. A total of 23 pregnant and 16 non-pregnant opioid-dependent patients were studied in two phases to evaluate pregnancy-dependent changes in methadone pharmacokinetics. In the first phase, pregnant patients had a statistically significant higher elimination rate constant (k) and lower half-life compared to non-pregnant controls. In the second phase, the apparent clearance (Cl/F) was significantly greater during pregnancy, with preliminary data suggesting that this observation results from a decrease in the fraction of dose absorbed (F). The implications of these findings on dosing regimens during pregnancy is discussed.
传统上，美沙酮维持治疗采用每日一次的给药方案。本研究评估了该方案在孕期的有效性。共对23名孕期和16名非孕期阿片类药物依赖患者分两个阶段进行研究，以评估孕期美沙酮药代动力学的变化。在第一阶段，与非孕期对照组相比，孕期患者的消除速率常数（k）在统计学上显著更高，半衰期更低。在第二阶段，孕期的表观清除率（Cl/F）显著更高，初步数据表明，这一观察结果是由于吸收剂量分数（F）降低所致。讨论了这些发现对孕期给药方案的影响。
