The term opioid refers to natural, semisynthetic and synthetic medications that relieve pain by binding to opioid receptors in the nervous system. The term includes all agonists and antagonists with morphine-like activity. Opioid switching is the change from one specific opioid to a different opiod or from one administration route to another if pain control is inadequate or side effects are a problem. Opioid switching has been studied in patients with refractory cancer pain. The National Comprehensive Cancer Network (NCCN) suggests consideration of opioid rotation or switching in the case of inadequate pain control, significant adverse events, or issues such as drug cost. Switching opioid route has been examined for its effect in managing constipation.
Tassinari, D., Sartori, S., Tamburini, E., Scarpi, E., Tombesi, P., Santelmo, C., & Maltoni, M. (2009). Transdermal fentanyl as a front-line approach to moderate-severe pain: A meta-analysis of randomized clinical trials. Journal of Palliative Care, 25, 172–180.
To compare transdermal fentanyl to slow-release oral morphine—in terms of safety, efficacy, and patient compliance—in patients who have stable opiate requirements for pain control
Of the 117 trials retrieved, 11 were considered potentially eligible. The analysis included five trials. Three trials included patients with cancer, and two included patients without cancer. The quality of the reports was evaluated using the Jadad scale.
Side-effect profiles of transdermal fentanyl and oral slow-release morphine differ, but in this analysis authors observed no significant differences in overall side effects and patient preference regarding the two approaches. Transdermal fentanyl appears to be a valid alternative to oral opiates.
Findings should be interpreted with caution, given the limitations of this meta-analysis. Additional research comparing transdermal and other medication delivery routes for pain control is warranted. Transdermal opiates may be particularly useful for patients using opiate switching. Addressing individual patients' needs and concerns may mean that side-effect profiles play an important role in the selection of a medication delivery route.
Ahmedzai, S., & Brooks, D. (1997). Transdermal fentanyl versus sustained-release oral morphine in cancer pain: Preference, efficacy, and quality of life. The TTS-Fentanyl Comparative Trial Group. Journal of Pain and Symptom Management, 13, 254–261.
To compare transdermal fentanyl and sustained-released morphine in palliative care patients with cancer by measuring efficacy, tolerance, and quality of life (QOL).
Patients received one treatment for 15 days, then the other for 15 days to compare which provided the greatest efficacy and QOL, and the fewest side effects. The null hypothesis was 50% of patients would prefer fentanyl and 50% would prefer morphine.
38 different palliative care centers in the United Kingdom
This was a randomized, open, two-period, crossover study.
Mazumdar, A., Mishra, S., Bhatnagar, S., & Gupta, D. (2008). Intravenous morphine can avoid distressing constipation associated with oral morphine: A retrospective analysis of our experience in 11 patients in the palliative care in-patient unit. American Journal of Hospice and Palliative Care, 25, 282–284.
To describe differences in bowel function with oral or IV opioids.
Patients who were admitted to a palliative inpatient unit for pain management had data retrospectively collected related to morphine-induced constipation. After IV morphine was administered and dose requirements were determined, patients were converted to oral morphine and then discharged.
The study has clinical applicability to end-of-life and palliative care.
This was a retrospective, descriptive study.
Visual analog scale
Patients on IV morphine were less likely to need laxative therapy to promote bowel function compared with patients on oral morphine. All patients on oral morphine needed laxative therapy.
Implications are limited because of the small sample size and other uncontrolled variables. More research is needed to determine whether IV morphine is less constipating than oral morphine and the applicability of this information in patient care.
Radbruch, L., Sabatowski, R., Loick, G., Kulbe, C., Kasper, M., Grond, S., & Lehmann, K.A. (2000). Constipation and the use of laxatives: A comparison between transdermal fentanyl and oral morphine. Palliative Medicine, 14, 111–119.
To investigate constipation and the use of laxatives in patients with chronic cancer pain treated with oral morphine and transdermal fentanyl.
Patients were switched from long-acting morphine to fentanyl patches. Fentanyl doses were calculated with a conversion table based on a 100:1 dose ratio. If the calculated fentanyl dose was higher than 2.4 mg/day = 100 ug/hour (more than 270 mg/day slow-release morphine), more than one patch was used. Patients were treated with oral slow-release morphine for at least six days (morphine phase) until they reported stable pain intensity scores of 40 or less on a visual analog scale (0 = no pain, 100 = worst pain imaginable) for at least two days. Analgesic therapy then was switched from oral morphine to transdermal fentanyl (fentanyl phase). Fentanyl patches were changed regularly after three days. Fentanyl doses were increased when patients reported inadequate pain relief or had to take more than six rescue medications per day. The study was terminated after 30 days of transdermal therapy. Patients who completed the study until day 17 or longer were included in an intraindividual comparison of laxative intake using the Wilcoxon rank test.
This was an open, sequential, multi-center study.
The use of laxatives was reduced significantly with transdermal fentanyl.
Wirz, S., Wittmann, M., Schenk, M., Schroeck, A., Schaefer, N., Mueller, M., . . . Nadstawek, J. (2009). Gastrointestinal symptoms under opioid therapy: A prospective comparison of oral sustained-release hydromorphone, transdermal fentanyl, and transdermal buprenorphine. European Journal of Pain, 13, 737-743.
To determine whether the transdermal opioids transdermal fentanyl (TDF) or transdermal buprenorphine (TDB) or oral sustained-release hydromorphone (OSRH) produced different gastrointestinal side effects.
Patients with nociceptive pain receiving one of the study drugs (TDF, TDB, or OSRH) over four weeks at a stable dose were identified. Medication adherence was checked daily.
This was a prospective, open-label, controlled study.
TD narcotics caused more constipation than oral hydromorphone.
In this study, TD narcotics caused more constipation than the oral narcotic.