Lack of Benefit From Paracetamol (Acetaminophen) for Palliative Cancer Patients Requiring High-Dose Strong Opioids: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial
Accepted 24 July 2009. published online 18 January 2010.
Abstract
Context
The adjunctive use of paracetamol (acetaminophen) with strong opioids has become entrenched practice in palliative care pain management, despite little evidence to support its use.
Objective
The study aim was to investigate potential analgesic benefits of 4g of paracetamol daily for palliative cancer patients requiring high-dose opioids.
Methods
Thirty-one patients, using at least 200mg of oral morphine equivalent daily, were recruited to a prospective, double-blinded, randomized, crossover trial. Patients received usual medications plus 4g of paracetamol or placebo for five days each in random order. Primary outcome, effect on pain, was assessed using daily diaries, including a numerical rating scale (NRS) from zero (no pain) to 10 (unbearable) and recording numbers of breakthrough analgesics. Secondary outcomes—nausea, vomiting, cognitive impairment, constipation, and overall well-being—were assessed using the NRS. Data from the last four days of each treatment were analyzed. Patients also indicated in which part of the study their pain was better controlled.
Results
Twenty-two patients, requiring a median dose of 255mg of oral morphine equivalent daily, completed the trial. There were no significant order or treatment-by-order interaction effects for any variable; paired t-tests were conducted to investigate change in mean levels on outcome variables with placebo vs. paracetamol. For none of the variables was there a statistically significant difference when assessed with placebo compared with paracetamol. No change approached clinically significant levels, with a mean difference in rated pain of 0.16, and mean difference of 0.42 for a number of breakthrough medications. Fifteen patients were undecided whether paracetamol improved pain.
Conclusions
These data do not support the common practice of adding regular paracetamol daily as an adjunct to high-dose opioids for pain control in cancer patients receiving palliative care.
aBrisbane South Palliative Care Collaborative, Brisbane, Queensland, Australia
bQueensland Health, Brisbane, Queensland, Australia
cGriffith University School of Medicine, Brisbane, Queensland, Australia
dMt. Olivet Palliative Services, Brisbane, Queensland, Australia
eBrisbane South Palliative Care Services, Brisbane, Queensland, Australia
fSchool of Psychology, University of Sydney, Sydney, New South Wales, Australia
Address correspondence to: Fiona J. Israel, RN, MCouns, Brisbane South Palliative Care Collaborative, P.O. Box 4069, Eight Mile Plains, Queensland 4113, Australia.
This research was supported by the Brisbane South Palliative Care Collaborative, a joint partnership between Queensland Health, Metro South Health Service District, Griffith University School of Medicine, and Mt. Olivet Community Services.
ABSTRACT