Intravenous methadone in the management of chronic cancer pain: safe and effective starting doses when substituting methadone for fentanyl.

摘要: BACKGROUND Patients often are rotated from other opioids to methadone when side effects occur before satisfactory analgesia is achieved. Various strategies have been proposed estimate safe and effective starting doses of rotating morphine hydromorphone; however, there no guidelines for estimating fentanyl. METHODS The authors prospectively observed 18 consecutive patients experiencing chronic pain cancer who underwent opioid rotation intravenous patient-controlled (PCA) with fentanyl PCA methadone. Patients were switched because uncontrolled associated sedation or confusion. A conversion ratio 25 μg/hour 0.1 mg/hour was used calculate the initial dose in all patients. RESULTS Mean scores decreased 8.1 4.8 on Day 1 after switch 3.22 4 switch. Mean 1.5 0.44 0.16 Days 4, respectively. Among 6 experienced confusion while switch, 5 improved within 2 days None toxicity methadone. CONCLUSIONS On basis this preliminary study, suggest that switching a may be effective. Cancer 2001;92:1919–25. © 2001 American Society.