Laxatives or methylnaltrexone for the management of constipation in palliative care patients

Background: Constipation is common in palliative care; it can generate considerable suffering due to the unpleasant physical symptoms. In the first Cochrane Review on effectiveness of laxatives for the management of constipation in palliative care patients, published in 2006, no conclusions could be drawn because of the limited number of evaluations. This article describes the first update of this review. / Objectives: To determine the effectiveness of laxatives or methylnaltrexone for the management of constipation in palliative care patients. / Search methods: We searched databases including MEDLINE and CENTRAL (The Cochrane Library) in 2005 and in the update to August 2010. / Selection criteria: Randomised controlled trials (RCTs) evaluating laxatives for constipation in palliative care patients. In the update we also included RCTs on subcutaneous methylnaltrexone; an opioid-receptor antagonist that is now licensed for the treatment of opioid-induced constipation in palliative care when response to usual laxative therapy is insufficient. / Data collection and analysis: Two authors assessed trial quality and extracted data. The appropriateness of combining data from the studies depended upon clinical and outcome measure homogeneity. / Main results: We included seven studies involving 616 participants; all under-reported methodological features. In four studies the laxatives lactulose, senna, co-danthramer, misrakasneham, and magnesium hydroxide with liquid paraffin were evaluated. In three methylnaltrexone. In studies comparing the different laxatives evidence was inconclusive. Evidence on subcutaneous methylnaltrexone was clearer; in combined analysis (287 participants) methylnaltrexone, in comparison with a placebo, significantly induced laxation at 4 hours (odds ratio 6.95; 95% confidence interval 3.83 to 12.61). In combined analyses there was no difference in the proportion experiencing side effects, although participants on methylnaltrexone suffered more flatulence and dizziness. No evidence of opioid withdrawal was found. In one study severe adverse events, commonly abdominal pain, were reported that were possibly related to methylnaltrexone. A serious adverse event considered to be related to the methylnaltrexone also occurred; this involved a participant having severe diarrhoea, subsequent dehydration and cardiovascular collapse. / Authors' conclusions: The 2010 update found evidence on laxatives for management of constipation remains limited due to insufficient RCTs. However, the conclusions of this update have changed since the original review publication in that it now includes evidence on methylnaltrexone. Here it found that subcutaneous methylnaltrexone is effective in inducing laxation in palliative care patients with opioid-induced constipation and where conventional laxatives have failed. However, the safety of this product is not fully evaluated. Large, rigorous, independent trials are needed

Review of the efficacy and safety of over-the-counter medicine

Over-the-counter medicines are available without prescription because of their safety and effectiveness, to treat minor ailments and symptoms. The objective of the study was to analyze the availability and quality of systematic reviews published about nonprescription medicines, identifying the groups for which there are gaps in evidence. We identified published articles through the Cochrane Database of Systematic Review and MEDLINE, from the start of the database until May 2012, using the search terms "nonprescription drugs," "over the counter," and "OTC." We searched for articles that describe systematic reviews addressing the efficacy and safety of drugs dispensed without a prescription, according to the lists published by the Association of the European Self-Medication Industry and in Brazil, in the clinical conditions listed in Groups and Specified Therapeutic Indications. We included 49 articles, 18 articles were of moderate quality and 31 of high quality. Of the studies, 74.5% demonstrated efficacy in favor of the use of drugs evaluated. Of the 24 studies that evaluated safety, 21% showed evidence unfavorable to the drug. Overall, the evidence found in the studies included in the overview is favorable to the use of the drugs evaluated. However, there are gaps in evidence for some therapy groups.</p