Beaver W T, Feise G A, Robb D
Clin Pharmacol Ther. 1981 Feb;29(2):174-80. doi: 10.1038/clpt.1981.28.
In a double-blind study using patients' subjective reports as indices of analgesia, the relative analgesic potency of intramuscular and oral nalbuphine was determined in 104 postoperative patients. Effects of single doses of 3 and 9 mg of intramuscular nalbuphine were compared with those of 15- and 45-mg oral doses of nalbuphine by means of a parallel study design (26 patients per treatment group). When both intensity and duration of analgesia are considered (i.e., total analgesic effect), oral nalbuphine is 1/4 to 1/5 as potent as intramuscular nalbuphine. In terms of peak effect, however, oral nalbuphine is only 1/10 as potent. The oral/parenteral potency ratio for total effect is close to those obtained by Houde et al. in studies of morphine (1/6), metopon (1/5), hydromorphone (1/5), and oxymorphone (1/6) and suggests that oral nalbuphine undergoes substantial biotransformation on first pass through gut mucosa and liver. Since intramuscular nalbuphine is approximately equipotent to morphine, it should be feasible to equal the analgesia induced by the usual intramuscular doses of morphine with reasonable oral doses of nalbuphine. Although nalbuphine is a mixed agonist/antagonist analgesic, no psychotomimetic reactions were observed.
在一项以患者主观报告作为镇痛指标的双盲研究中，对104例术后患者测定了肌肉注射和口服纳布啡的相对镇痛效力。采用平行研究设计（每个治疗组26例患者），比较了3毫克和9毫克肌肉注射纳布啡单剂量与15毫克和45毫克口服纳布啡单剂量的效果。当同时考虑镇痛强度和持续时间（即总镇痛效果）时，口服纳布啡的效力仅为肌肉注射纳布啡的1/4至1/5。然而，就峰值效应而言，口服纳布啡的效力仅为1/10。总效应的口服/胃肠外效力比与霍德等人在吗啡（1/6）、美托酮（1/5）、氢吗啡酮（1/5）和羟吗啡酮（1/6）研究中获得的比值相近，这表明口服纳布啡在首次通过肠黏膜和肝脏时会发生大量生物转化。由于肌肉注射纳布啡的效力与吗啡大致相当，因此用合理的口服剂量纳布啡来达到通常肌肉注射吗啡剂量所诱导的镇痛效果应该是可行的。尽管纳布啡是一种混合激动剂/拮抗剂镇痛药，但未观察到拟精神病反应。
