Two strategies effectively relieve OBD without interfering with centrally mediated analgesia: the administration of opioid antagonists with limited systemic absorption and peripherally acting mu-opioid receptor antagonists (PAMORA) that selectively target mu-receptors in the gastrointestinal tract. Methylnaltrexone and alvimopan are two recently marketed PAMORA and provide a new mechanism-based approach for the treatment of opioid-induced gastrointestinal dysfunction. However, its use in clinical practice is limited by various reasons such as its relatively low response rates and higher costs. Nevertheless, at least four new oral PAMORA (NKTR-118, TD-1211, ADL-7445, and ADL-5945) are under clinical development, further expanding the possibilities for a new paradigm for OBD management.

In April 2008, the US FDA granted approval to methylnaltrexone (Relistor), the first peripheral micro-opioid-receptor antagonist for the treatment of opioid-induced constipation in advanced-illness patients receiving palliative care and for whom other laxative therapies failed to achieve adequate results. Methylnaltrexone, a quaternary derivative of naltrexone, introduces a novel mechanism of action that selectively antagonizes the peripheral micro-receptors in the GI tract without effects on the CNS. In clinical trials, subcutaneous methylnaltrexone reversed opioid-induced constipation after the first dose in approximately 50-60% of the patients. In most of the cases, effective laxation occurred within 1 h. The therapeutic benefit was sustained in multiple-dose studies. Owing to the nature of the population studied, safety data are available for approximately 4 months of use. Although it is not the focus of this article, methylnaltrexone's mechanism of action suggests it could be beneficial for other peripheral, opioid-induced adverse effects, such as opioid-related nausea, vomiting, urinary retention, pruritus or postoperative ileus.

ObjectivesThe aim of this study was to assess the quality and readability of patient drug information published on a corporate website and written by a multidisciplinary team including pharmacists, doctors, nurses, journalists, experts in healthcare communication, and patients. Documents were user-tested with patients in order to improve and adapt the final product.MethodsReadability was measured using the INFLESZ tool, a software developed from the Flesch formula and adapted to Spanish. DISCERN and EQIP were used for quality appraisal by two independent raters as they have shown to be useful and consistent for assessing information related to treatment and treatment choices.ResultsMost of the documents (>67%) had an easy readability level, implying that they would be easily understood by a person with a primary school education level. The DISCERN tool showed higher reliability and concordance than EQIP. The overall DISCERN mean score for the documents was 55.4% for rater 1% and 51% for rater 2, implying very good quality.ConclusionsThis retrospective analysis supports the implemented workflow of the multidisciplinary team and the user-testing process and encourages continuation of this systematic development of documents. Although both EQIP and DISCERN are useful and widely used tools, according to our results we would favour DISCERN to evaluate patient drug information.