
(5α,6α)-7,8-didehydro-4,5-epoxy-17-methylmorphinan-3,6-diol
2.長期使用或高劑量使用時,孕婦分級為D。
2. Morphine HCI注射劑:a.肌肉或皮下注射:成人10mg(5~20mg)每4小時。兒童0.1~0.2mg/kg(最高15mg)每4小時。b.靜脈注射:成人2.5~5mg溶於4~5ml注射用水中,緩慢注射4~5分鐘。速度太快會增加不良反應的發生率。c.持續靜脈輸注:用5%dextrose液稀釋或0.1~1mg/ml以流速控制器輸注。
Absorption:Mean Tmax is 3.7h and mean Cmax is 9.9 to 27.4 ng/mL (dose dependent) for sustained-release form. Bioavailability is approximately 40%.
Distribution:Morphine distributes to skeletal muscle, kidneys, liver, intestinal tract, lungs, spleen, and brain; crosses the placental membrane and is found in breast milk.
Metabolism:Virtually all converted into glucuronide metabolites; small fraction is demethylated in the liver. Major metabolite is morphine-3-glucuronide (55% to 75%).
Elimination:The t½ is approximately 2 to 4 h.
Onset:Onset is 15 to 60 min (intrathecal/epidural).
Duration:Duration is 3 to 7 h.
Antihistamines, chloral hydrate, glutethimide, methocarbamol
Depressant effects of morphine may be enhanced.
Cimetidine
Monitor for increased respiratory and CNS depression. Concomitant administration of cimetidine and morphine has been reported to precipitate apnea, confusion, and muscle twitching in an isolated report.
Clomipramine, nortriptyline, amitriptyline
Monitor for increased CNS and respiratory depression when administered with morphine.
CNS depressants (eg, alcohol, sedatives, tranquilizers)
Additive CNS depression.




