The role of methadone in opioid rotation—a Polish experience
ABSTRACT To assess methadone analgesia, adverse effects, and calculation method of equianalgesic doses with oral morphine.
Methadone was administered to 21 opioid-tolerant cancer patients because of pain (numerical rating scale [NRS] > 5) on morphine (ten patients), transdermal fentanyl (TF; four patients), morphine, ketamine, and TF (one patient), tramadol (one patient), pethidine (one patient), pain with drowsiness on morphine with ketamine (three patients), and pain with nausea on morphine (one patient). Dose ratios of equivalent daily dose of oral morphine (ddom) to daily dose of oral methadone (ddomet) were 4:1 (ddom to 100 mg), 6:1 (101-300 mg), 12:1 (301-1,000 mg), and 20:1 (over 1,000 mg). Previous opioid treatment was stopped completely (stop-start approach) in 19 patients; two received methadone and other opioids. The mean ddom before switch was 812 +/- 486 mg. Methadone was administered regularly three times daily; 20 patients received oral methadone, one patient received rectal suppositories. Breakthrough pain was treated with methadone (half of regular dose), morphine, fentanyl, metamizol, ketoprofen, or ketamine.
Mean time of methadone treatment was 38.3 +/- 27.1 days (range 3-95 days), mean daily doses: start 48.1 +/- 19.7 mg, maximal 148.5 +/- 104.1 mg, treatment completion 131.1 +/- 104.3 mg. Good analgesia (NRS < 4) was observed in 11 patients, partial (NRS 4-5) in nine patients, and unsatisfactory (NRS > 5) in one patient. Adverse effects such as drowsiness (six patients), constipation (six patients), nausea and vomiting (two patients), sweating (two patients), and respiratory depression (one patient) the last one resolved by methadone cessation and naloxone.
Results confirmed high analgesic efficacy, acceptable methadone adverse event profile, safety, and effectiveness of ddom to ddomet dose calculation method.
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ABSTRACT: Patients requiring chronic opioid therapy may not respond to or tolerate the first opioid prescribed to them, necessitating rotation to another opioid. They may also require dose increases for a number of reasons, including worsening disease and increased pain. Dose escalation to restore analgesia using the primary opioid may lead to increased adverse events. In these patients, rotation to a different opioid at a lower-than-equivalent dose may be sufficient to maintain adequate tolerability and analgesia. In published trials and case series, opioid rotation is performed either using a predetermined substitute opioid with fixed conversion methods, or in a manner that appears to be no more systematic than trial and error. In clinical practice, opioid rotation must be performed with consideration of individual patient characteristics, comorbidities (eg, concurrent psychiatric, pulmonary, renal, or hepatic illness), and concurrent medications, using flexible dosing protocols that take into account incomplete opioid cross-tolerance. References cited in this review were identified via a search of PubMed covering all English language publications up to May 21, 2013 pertaining to opioid rotation, excluding narrative reviews, letters, and expert opinion. The search yielded a total of 129 articles, 92 of which were judged to provide relevant information and subsequently included in this review. Through a review of this literature and from the authors' empiric experience, this review provides practical information on performing opioid rotation in clinical practice.
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ABSTRACT: Chronic pain affects up to 50 million Americans every day. Traditional treatment has included acetaminophen, nonsteroidal antiinflammatory drugs (NSAIDs), or opioids. The combination of NSAIDs and opioids can provide effective treatment for up to 90% of patients with chronic pain, but the NSAIDs have the potential for significant, even life-threatening side effects. Additionally, the nonselective cyclooxygenase inhibitors with 16,000 deaths per year in the United States might not be any safer. The opioids are great for short-term pain, but may need to be adjusted or changed frequently due to the development of tolerance. Understanding of the mechanism of opioids and NSAIDs has improved greatly over the past decade, but is still incomplete.Seminars in Interventional Radiology 12/2010; 27(4):400-11. DOI:10.1055/s-0030-1267855
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ABSTRACT: <⁄span> Methadone is one of the most important medications used for the treatment of refractory pain in the palliative care setting, and is usually initially prescribed by one of a limited number of physicians who have acquired authorization for its use. A lack of authorized physicians able to take over prescribing when the patient is stable is a barrier to accessing methadone for analgesia. <⁄span> To determine the barriers to family physicians becoming authorized to prescribe methadone for pain in palliative care. <⁄span> A survey exploring the perceived barriers to continuing methadone for pain in palliative care following initial prescription by a specialist was mailed to a randomly selected group of 870 family physicians in British Columbia. <⁄span> The response rate was 30.9%. Of the 204 responding physicians, 76.1% described themselves as positioned to provide ongoing palliative care to their patients. Within this group, 38 (18.6%) were already authorized to prescribe methadone for pain. The remaining 166 (81.4%) had significant knowledge deficits regarding methadone use in palliative care, but were largely aware of their deficits, and more than one-half were willing to learn more and to obtain an authorization if requested. <⁄span> Responding family physicians had mostly received little education regarding methadone for pain, but were aware of their need for education and were willing to learn. Physicians who had already become authorized were generally satisfied with the process of authorization, and believed the process of education through authorization was appropriate and not onerous.Pain research & management: the journal of the Canadian Pain Society = journal de la societe canadienne pour le traitement de la douleur 18(2):83-6. · 1.39 Impact Factor