Clinical trial: phase 2 study of lubiprostone for irritable bowel syndrome with constipation

Nocebo effects and influencing factors in the randomized clinical trials of chronic constipation: A systematic review and meta-analysis

BACKGROUND

Nocebo effects are unavoidable in randomized clinical trials. We aimed to assess the magnitude of nocebo effects and explore the influencing factors in chronic constipation.

METHODS

We searched the PubMed, Embase, and Cochrane Library databases up to July 2022. Randomized, placebo-controlled trials investigating interventions in chronic constipation were included. We conducted a random effects meta-analysis of the proportion of adverse events (AEs) in placebo-treated participants and evaluated the effect of trial characteristics on nocebo effects.

KEY RESULTS

We identified 20,204 studies from the databases, of which 61 were included in the final analysis. The pooled placebo AE rate was 30.41%, and AE-related withdrawal rate was 1.53%. The most commonly reported AEs were headache (5.67%), diarrhea (4.45%), abdominal pain (3.98%), nasopharyngitis (3.39%), nausea (3.36%), and flatulence (2.95%). The placebo AE rate was lower in trials conducted in Asia compared to those in Europe, North America, and international trials. It was also lower in trials diagnosed by Rome III compared to clinician's opinion and Rome II. Additionally, the placebo AE rate was lower in single-center trials compared to multicenter trials, lower in 5-8 weeks therapy compared to 9-12 weeks therapy, lower in participants with FC compared to those with IBS-C and CC, lower in trials with 2 arms compared to 3 arms, and higher in trials with prokinetic drugs compared to secretagogues and laxatives.

CONCLUSIONS & INFERENCES

The placebo AE rate was 30.41% in patients with chronic constipation. Based on our findings, we recommend that researchers take the nocebo effects into consideration when designing and conducting clinical trials and adopt specific measures to mitigate the negative influence of nocebo effects.

The ClC-2 Chloride Channel Activator, Lubiprostone, Improves Intestinal Barrier Function in Biopsies from Crohn’s Disease but Not Ulcerative Colitis Patients

The prostone analog, lubiprostone, is approved to manage constipation-predominant irritable bowel syndrome. Lubiprostone also protects intestinal mucosal barrier function in animal models of colitis. The aim of this study was to determine if lubiprostone improves barrier properties in isolated colonic biopsies from Crohn’s disease (CD) and ulcerative colitis (UC) patients. Sigmoid colon biopsies from healthy subjects, CD and UC patients in remission, and CD patients with active disease were mounted in Ussing chambers. Tissues were treated with lubiprostone or vehicle to determine the effects on transepithelial electrical resistance (TER), FITC-dextran 4kD (FD4) permeability, and electrogenic ion transport responses to forskolin and carbachol. Localization of the tight junction protein, occludin, was determined by immunofluorescence. Lubiprostone significantly increased ion transport across control, CD and UC remission biopsies but not active CD. Lubiprostone selectively improved TER in both CD remission and active disease biopsies but not in control or UC biopsies. The improved TER was associated with increased membrane localization of occludin. Lubiprostone selectively improved barrier properties of biopsies from CD patients vs. UC and independent of an ion transport response. These data indicate that lubiprostone has potential efficacy in improving mucosal integrity in Crohn’s disease.

Italian guidelines for the management of irritable bowel syndrome: Joint Consensus from the Italian Societies of: Gastroenterology and Endoscopy (SIGE), Neurogastroenterology and Motility (SINGEM), Hospital Gastroenterologists and Endoscopists (AIGO), Digestive Endoscopy (SIED), General Medicine (SIMG), Gastroenterology, Hepatology and Pediatric Nutrition (SIGENP) and Pediatrics (SIP)

The irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction. IBS is still associated with areas of uncertainties, especially regarding the optimal diagnostic work-up and the more appropriate management. Experts from 7 Italian Societies conducted a Delphi consensus with literature summary and voting process on 27 statements. Recommendations and quality of evidence were evaluated using the grading of recommendations, assessment, development, and evaluation (GRADE) criteria. Consensus was defined as >80% agreement and reached for all statements. In terms of diagnosis, the consensus supports a positive diagnostic strategy with a symptom-based approach, including the psychological comorbidities assessment and the exclusion of alarm symptoms, together with the digital rectal examination, full blood count, C-reactive protein, serology for coeliac disease, and fecal calprotectin assessment. Colonoscopy should be recommended in patients with alarm features. Regarding treatment, the consensus strongly supports a dietary approach for patients with IBS, the use of soluble fiber, secretagogues, tricyclic antidepressants, psychologically directed therapies and, only in specific IBS subtypes, rifaximin. A conditional recommendation was achieved for probiotics, polyethylene glycol, antispasmodics, selective serotonin reuptake inhibitors and, only in specific IBS subtypes, 5-HT3 antagonists, 5-HT4 agonists, bile acid sequestrants.

Cannabidiol for Functional Dyspepsia With Normal Gastric Emptying: A Randomized Controlled Trial

INTRODUCTION

Cannabidiol (CBD), a CBR2 agonist with limited psychic effects, antagonizes CB1/CB2 receptors. Allelic variation CNR1 (gene for CBR1) rs806378 and FAAH rs324420 were associated with altered gut motility and sensation. This study aimed to compare the pharmacodynamics and clinical effects of a 4-week treatment with pharmaceutical-grade CBD vs placebo and assess the interactions of FAAH and CNR1 gene variants on the effects of CBD in patients with functional dyspepsia (FD).

METHODS

We performed a randomized, double-blinded, placebo-controlled (1:1 ratio) study of CBD b.i.d. (20 mg/kg/d according to the US Food and Drug Administration escalation guidance) in FD patients with nondelayed gastric emptying (GE) at baseline. Symptoms were assessed by validated daily symptom diary (0-4 scale for upper abdominal pain, nausea, and bloating), weekly assessment of adequate relief, Leuven Postprandial Distress Scale (8 symptoms, adjectival scores rated 0-4 for severity), and quality of life (Short-Form Nepean Dyspepsia Index [average of 10 dimensions each on a 5-point scale]). After the 4-week treatment, all patients underwent measurements of GE of solids, gastric volumes, and Ensure nutrient satiation test. Statistical analysis compared 2 treatments for all endpoints and the effects of CBD in association with FAAH rs324420 and CNR1 rs806378.

RESULTS

CBD and placebo effects on physiological functions and patient response outcomes were not significantly different. There were borderline CBD treatment-by-genotype interactions: rs806378 CNR1 with Leuven Postprandial Distress Scale ( P = 0.06) and GE solids ( P = 0.12).

DISCUSSION

Approved doses of CBD used off-label do not relieve FD with normal baseline GE of solids or alter gastric motor functions and satiation. CBD treatment-by-gene interactions suggest potential benefits for postprandial distress with CNR1 rs806378 T allele.

Adverse events in trials of licensed drugs for irritable bowel syndrome with constipation or diarrhea: Systematic review and meta-analysis

BACKGROUND

Nocebo effects occurring in patients receiving placebo frequently impact on adverse events reported in randomized controlled trials (RCTs) in irritable bowel syndrome (IBS). Therefore, we conducted a systematic review and meta-analysis to assess the proportion of patients randomized to placebo or active drug experiencing any adverse event in trials of licensed drugs for IBS with constipation (IBS-C) or diarrhea (IBS-D), and to estimate the risk of developing adverse events among patients randomized to placebo.

METHODS

We searched MEDLINE, EMBASE CLASSIC and EMBASE, and the Cochrane central register of controlled trials (through June 2021) to identify RCTs comparing licensed drugs with placebo in adults with IBS-C or IBS-D. We generated Forest plots of pooled adverse event rates in both active drug and placebo arms and pooled risk differences (RDs) with 95% confidence intervals (CIs).

KEY RESULTS

There were 21 RCTs of licensed drugs versus placebo in IBS-C (5953 patients placebo) and 17 in IBS-D (3854 patients placebo). Overall, 34.9% and 46.9% of placebo patients in IBS-C and IBS-D trials, respectively, developed at least one adverse event, with a statistically significantly higher risk of any adverse event and withdrawal due to an adverse event with active drug. In IBS-C and IBS-D trials, rates of each individual adverse event were generally higher with active drug. However, in IBS-C trials, only diarrhea or headache was significantly more common with active drug (RD 0.066 (95% CI 0.043-0.088) and RD 0.011 (95% CI 0.002-0.021), respectively), and in IBS-D trials only constipation, nausea, or abdominal pain (RD 0.096 (95% CI 0.054-0.138), 0.014 (95% CI 0.002-0.027), and 0.018 (95% CI 0.002-0.034), respectively).

CONCLUSIONS & INFERENCES

Patients with IBS randomized to placebo have a high risk of reporting adverse events, which might relate to both nocebo and non-nocebo factors. Although patients' expectations and psychosocial factors may be involved, further understanding of the mechanisms are important to control or optimize these effects in RCTs, as well as in clinical practice.

Improvement in constipation and diarrhea is associated with improved abdominal pain in patients with functional bowel disorders

BACKGROUND

Abdominal pain is a bothersome and lifestyle limiting symptom in patients with functional bowel disorders. It is associated with decreased quality of life in affected individuals, as well as significant annual healthcare expenditure. Knowledge of specific factors that predict improvement in abdominal pain in those with functional bowel disorders is thus far limited.

METHODS

Consecutive patients presenting for outpatient care at a major academic medical center between October 2017 and March 2020 completed an electronic symptom survey prior to initial clinic visit, and again after 3 months. The Rome IV questionnaires for functional dyspepsia, irritable bowel syndrome, functional constipation, and functional diarrhea were all included. Additionally, all subjects completed the Patient Reported Outcomes Measurement Information System Anxiety, Depression, and sleep disturbance questionnaires. Patients with a diagnosis of a Rome IV functional gastrointestinal disorder without any organic cause for symptoms were identified based on both chart review as well as survey response data. Univariable and multivariable analysis was used to assess predictors of improved abdominal pain after 3 months.

KEY RESULTS

180 patients with a mean age of 45.3 years were included in the final analysis. 78.3% of patients were female, and 77.2% met Rome IV criteria for irritable bowel syndrome. On multivariable analysis, improvement in constipation and diarrhea were both independent predictors of improved abdominal pain after 3 months.

CONCLUSIONS AND INFERENCES

Improvement in constipation and diarrhea both predicted improvement in abdominal pain, suggesting that addressing these factors is central to the management of abdominal pain in functional gastrointestinal disorders.

Cost of Constipation: A New Look With a Focus on New Medications

GOAL

The study was designed to assess drug costs for constipation therapy and to relate costs to markers of functional status.

BACKGROUND

Secretagogues have been introduced as new agents for the treatment of constipation. Previously published modeling studies suggested that improved productivity lowers the indirect disease burden and balances the higher drug costs.

STUDY

Data were abstracted from the publicly available Medical Expenditure Panel Survey to identify adults with a functional gastrointestinal disorder who received a prescription for laxatives or secretagogues covering >2 days. Demographic data, recorded health care utilization and cost, and markers of functional status were extracted for the years from 2005 to 2017 to determine differences between participants treated with secretagogues or laxatives.

RESULTS

The cohort of 2006 persons was female predominant [67.8%; age: 56.9 (55.8-57.9) years] and spent $92.89 (75.68-110.10) for medications treating constipation. The use of secretagogues (10.3% of the cohort) was the best independent predictor of constipation treatment costs. Using quality of life measures, perceived limitations in activities or work, and absenteeism, there was no difference between participants receiving laxatives and those taking secretagogues.

CONCLUSION

Using survey data designed to be representative of the United States population, the study identified secretagogues as a key cost factor in drug treatment of constipation. The results do not support models suggesting improved role functioning offsets these higher direct expenditures. While prospective comparative studies are needed to more definitively correlate costs with direct or indirect benefits of different agents, limiting the use of more expensive medications to otherwise refractory cases may help to reign in the spiraling health care costs in this country.

Diarrhea-Predominant and Constipation-Predominant Irritable Bowel Syndrome: Current Prescription Drug Treatment Options

Irritable bowel syndrome (IBS) is a heterogenous disease with a variety of therapeutic options, including eight prescription drugs approved for use in IBS in the USA. Choosing among the myriad treatment options requires attention to patient preferences both on clinical outcomes and costs associated with treatment. We performed a narrative review of the literature to summarize these important determinants of treatment choice including: labeled indications; clinical profiles of efficacy, safety, and tolerability of prescription drugs; and cost-effectiveness for diarrhea-predominant IBS drugs (IBS-D: alosetron, eluxadoline, and rifaximin) and constipation-predominant IBS drugs (IBS-C: linaclotide, lubiprostone, plecanatide, tegaserod, and tenapanor). We then review the standard model of shared decision-making aimed at guiding an informed, patient-centered discussion to integrate comparative clinical and cost outcomes toward choosing an IBS treatment in practice.

Efficacy and safety of lubiprostone for the treatment of functional constipation in Chinese adult patients: A multicenter, randomized, double-blind, placebo-controlled trial

OBJECTIVES

Functional constipation is a gastrointestinal disorder prevalent around the world. Lubiprostone is the first locally acting type-2 chloride channel activator to be used for treating constipation. This study aimed to evaluate the efficacy and safety of lubiprostone in Chinese adults with functional constipation.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled study. Patients with functional constipation were randomized to receive either lubiprostone (24 mcg twice daily) or placebo for 4 weeks. The primary end-point was the frequency of spontaneous bowel movements (SBMs) during the first week of treatment. The secondary end-points included the median time of the first SBM, SBM frequency at weeks 2, 3 and 4, weekly response rate of SBMs, the stool consistency score and average number of complete spontaneous bowel movements (CSBMs) per week.

RESULTS

In total, 259 patients were randomized, with 130 in the lubiprostone group and 129 in the placebo group. SBM frequency was higher in the lubiprostone group (4.88 ± 4.09/wk) than that in the placebo group (3.22 ± 2.01/wk) at week 1 (P < 0.0001). SBM frequency was also higher in the lubiprostone group at weeks 2, 3 and 4. The average number of CSBMs and the stool consistency score in the lubiprostone group were significantly higher than that in the placebo group at each week. No drug-related serious adverse events (AEs) occurred. The most commonly reported AE was nausea.

CONCLUSION

Lubiprostone was superior to placebo in treating Chinese patients with functional constipation, together with good safety profile.

Present and Future Therapeutic Approaches to Barrier Dysfunction

There is converging and increasing evidence, but also uncertainty, for the role of abnormal intestinal epithelial barrier function in the origin and development of a growing number of human gastrointestinal and extraintestinal inflammatory disorders, and their related complaints. Despite a vast literature addressing factors and mechanisms underlying changes in intestinal permeability in humans, and its connection to the appearance and severity of clinical symptoms, the ultimate link remains to be established in many cases. Accordingly, there are no directives or clinical guidelines related to the therapeutic management of intestinal permeability disorders that allow health professionals involved in the management of these patients to carry out a consensus treatment based on clinical evidence. Instead, there are multiple pseudoscientific approaches and commercial propaganda scattered on the internet that confuse those affected and health professionals and that often lack scientific rigor. Therefore, in this review we aim to shed light on the different therapeutic options, which include, among others, dietary management, nutraceuticals and medical devices, microbiota and drugs, and epigenetic and exosomes-manipulation, through an objective evaluation of the scientific publications in this field. Advances in the knowledge and management of intestinal permeability will sure enable better options of dealing with this group of common disorders to enhance quality of life of those affected.

Evaluation of efficacy and safety of lubiprostone in patients with chronic constipation

OBJECTIVES

Lubiprostone is an apical type 2 chloride channel activator approved for the treatment of chronic constipation (CC), and nausea is the most common adverse symptom. However, the associated factors with the efficacy and the precise mechanism of nausea remain unclear. The aim of this study is to characterize clinical backgrounds related with the efficacy and the adverse symptoms of lubiprostone.

MATERIALS AND METHODS

Subjects were patients with CC who were prescribed lubiprostone from April 2017 to October 2019. The efficacy and safety of lubiprostone were retrospectively examined using the electronic medical record.

RESULTS

Hundred and fifty-five patients (76 men, and mean age 69) were evaluated. Lubiprostone was effective in 74 patients (47.8%), and the discontinuation due to adverse in 34 patients (21.9%). including nausea, diarrhea and abdominal pain in 16, 12 and 3 patients, respectively. The efficacy was significantly associated with gender, age, body mass index (BMI), diabetes mellitus, hypertension, calcium channel blockers and antipsychotics. In multivariate analysis, the efficacy was significantly associated with men (odds ratio [OR], 3.21; 95% confidence interval (CI), 1.42-7.27) and BMI (OR, 1.14; 95% CI, 1.02-1.28). The incidence of nausea was higher in patients under 65 years old, and hypertension was the significant protective factor for nausea.

CONCLUSIONS

Lubiprostone was effective for men patients with CC, and hypertension seems to be the protective factor for nausea.

Review article: diagnosis, management and patient perspectives of the spectrum of constipation disorders

BACKGROUND

Chronic constipation is a common, heterogeneous disorder with multiple symptoms and pathophysiological mechanisms. Patients are often referred to a gastroenterology provider after laxatives fail. However, there is limited knowledge of the spectrum and management of constipation disorders.

AIM

To discuss the latest understanding of the spectrum of constipation disorders, tools for identifying a pathophysiologic-based diagnosis in the specialist setting, treatment options and the patient's perspective of constipation.

METHODS

Literature searches were conducted using PubMed for constipation diagnostic criteria, diagnostic tools and approved treatments. The authors provided insight from their own practices.

RESULTS

Clinical assessment, stool diaries and Rome IV diagnostic criteria can facilitate diagnosis, evaluate severity and distinguish between IBS with constipation, chronic idiopathic constipation and dyssynergic defecation. Novel smartphone applications can help track constipation symptoms. Rectal examinations, anorectal manometry and balloon expulsion, assessments of neuromuscular function with colonic transit time and colonic manometry can provide mechanistic understanding of underlying pathophysiology. Treatments include lifestyle and diet changes, biofeedback therapy and pharmacological agents. Several classes of laxatives, as well as prokinetic and prosecretory agents, are available; here we describe their mechanisms of action, efficacy and side effects.

CONCLUSIONS

Constipation includes multiple overlapping subtypes identifiable using detailed history, current diagnostic tools and smartphone applications. Recognition of individual subtype(s) could pave the way for optimal, evidence-based treatments by a gastroenterology provider.

Impact of Electroacupuncture Stimulation on Postoperative Constipation for Patients Undergoing Brain Tumor Surgery

BACKGROUND

Constipation is frequently encountered in patients undergoing brain tumor resection. Constipation has negative effects on daily living, well-being, and individuals' quality of life. We examined the impact of acupuncture and electroacupuncture (EA) stimulation on postoperative constipation for patients undergoing brain tumor resection.

METHODS

Patients undergoing brain tumor resection (n = 150) were randomly divided into a nontreatment group, an acupuncture group, and an EA group. Rome III Diagnostic Criteria, Cleveland Clinic Constipation Score, symptom assessment, Patient Assessment of Constipation Quality of Life questionnaire, Self-Rating Anxiety Scale, and a Self-Rating Depression Scale were collected.

RESULTS

Acupuncture and EA were effective in relieving postoperative constipation. Electroacupuncture decreased constipation and improved quality of life scores.

CONCLUSION

Acupuncture and EA are novel adjuvant therapies to treat constipation.

Targeted pharmacotherapy of irritable bowel syndrome

PURPOSE OF REVIEW

Irritable bowel syndrome (IBS) is a highly prevalent functional gastrointestinal (GI) disorder with negative impact on quality of life and it represents a substantial economic burden on healthcare cost. The medical management of IBS is symptom directed. This review provides an update related to clinical trial data for novel treatment modalities in IBS targeting the gut epithelium secretagogue receptors and channels.

RECENT FINDINGS

The new Rome IV criteria define functional gastrointestinal disorders (FGID) as disorders of the gut-brain interaction. Pharmacological treatment modalities for IBS target gastrointestinal receptors and ion channels, peripheral opioid receptor, gut serotonin receptors, and the gut microbiome. New targeted pharmacotherapies have shown efficacy and safety in the treatment of patients with IBS.

SUMMARY

Diagnostic criteria for FGID, including IBS, have been revised in Rome IV and are defined as gut-brain disorders. Newly approved pharmacotherapy options with proven efficacy and acceptable side-effect profiles are available for the symptom-based management of IBS.

Pharmacologic, Dietary, and Psychological Treatments for Irritable Bowel Syndrome With Constipation: Cost Utility Analysis

Introduction. Irritable bowel syndrome (IBS) is the most common gastroenterology referral and one of the most common gastrointestinal complaints in primary care. We performed a cost-utility analysis of the most common treatments available in general practice for IBS with constipation (IBS-C), the most expensive IBS subtype. Methods. We developed a decision analytic model evaluating guideline-recommended and Food and Drug Administration-approved drugs, supplements, and dietary/psychological interventions. Model inputs were derived from "global symptom improvement" outcomes in systematic reviews of clinical trials. Costs were derived from national datasets. Analysis was performed with a 1-year time horizon from patient and payer perspectives. We analyzed a prototypical managed-care health plan with no cost-sharing to the patient. Results. From a payer perspective, global IBS treatments (including low FODMAP, cognitive behavioral therapy [CBT], neuromodulators), which are not specific to the IBS-C bowel subtype were less expensive than on-label prescription drug treatments. From a patient perspective, on-label prescription drug treatment with linaclotide was the least expensive treatment strategy. Drug prices and costs to manage untreated IBS-C were most important determinants of payer treatment preferences. Effects of treatment on missed work-days and need for repeated appointments to complete treatment were the most important determinants of treatment preference to patients. Discussion. Due mostly to prescription drug prices, neuromodulators, low FODMAP, and CBT appear cost-effective compared to on-label drug treatments from a payer perspective in cost-utility analysis. These findings may explain common treatment barriers in clinical practice.

ACG Clinical Guideline: Management of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a highly prevalent, chronic disorder that significantly reduces patients' quality of life. Advances in diagnostic testing and in therapeutic options for patients with IBS led to the development of this first-ever American College of Gastroenterology clinical guideline for the management of IBS using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Twenty-five clinically important questions were assessed after a comprehensive literature search; 9 questions focused on diagnostic testing; 16 questions focused on therapeutic options. Consensus was obtained using a modified Delphi approach, and based on GRADE methodology, we endorse the following: We suggest that a positive diagnostic strategy as compared to a diagnostic strategy of exclusion be used to improve time to initiating appropriate therapy. We suggest that serologic testing be performed to rule out celiac disease in patients with IBS and diarrhea symptoms. We suggest that fecal calprotectin be checked in patients with suspected IBS and diarrhea symptoms to rule out inflammatory bowel disease. We recommend a limited trial of a low fermentable oligosaccharides, disacchardies, monosaccharides, polyols (FODMAP) diet in patients with IBS to improve global symptoms. We recommend the use of chloride channel activators and guanylate cyclase activators to treat global IBS with constipation symptoms. We recommend the use of rifaximin to treat global IBS with diarrhea symptoms. We suggest that gut-directed psychotherapy be used to treat global IBS symptoms. Additional statements and information regarding diagnostic strategies, specific drugs, doses, and duration of therapy can be found in the guideline.

Systematic review with meta-analysis: lubiprostone efficacy on the treatment of patients with constipation

BACKGROUND

Lubiprostone is a type 2 chloride channel activator that has been shown to be efficacious and safe in the treatment for chronic constipation.

OBJECTIVE

To systematically review randomized clinical trials (RCTs) assessing efficacy of lubiprostone for patients with chronic idiopathic constipation (CIC), irritable bowel syndrome with predominant constipation (IBS-C) and opioid-induced constipation (OIC).

METHODS

Searches were conducted in PubMed, LILACS, Cochrane Collaboration Database, and Centre for Reviews and Dissemination. Lubiprostone RCTs reporting outcomes of spontaneous bowel movements (SBM) and abdominal pain or discomfort were deemed eligible. Meta-analysis was performed calculating risk ratios and 95% confidence intervals, using the Mantel-Haenszel method and random effects model.

RESULTS

Searches yielded 109 records representing 93 non-duplicate publications, and 11 RCTs (978 CIC, 1,366 IBS-C, 1,300 OIC, total = 3,644) met inclusion criteria. Qualitative synthesis showed that for CIC patients, lubiprostone is superior to placebo in terms of SBM outcomes. Meta-analysis for CIC was feasible for full responder and SBM within 24h rates, indicating superiority of lubiprostone over placebo. For IBS-C, lubiprostone was significantly superior for all SBM outcomes in follow-ups ranging from 1 week-3 months. In terms of abdominal pain, lubiprostone provided significantly better symptoms relief, particularly after 1 month of treatment. For OIC, lubiprostone was more effective than placebo for both SBM and discomfort measures.

CONCLUSION

Our findings demonstrated that lubiprostone is superior to placebo in terms of SBM frequency for CIC, IBS-C and OIC. In terms of abdominal symptoms, the most pronounced effect was seen for abdominal pain in IBS-C patients.

Medications for constipation in 2020

PURPOSE OF REVIEW

Chronic constipation is a common problem that substantially impacts the quality of life of patients and families, healthcare professionals, and resources. The purpose of this review is to discuss the medications that are available for management of chronic constipation, including medications that have been approved by the FDA for adults, other been studied in pediatrics now, and might become available within the upcoming years.

RECENT FINDINGS

Recent developments in the evaluation of childhood constipation are providing a better understanding into defecation disorders in children and not only new therapies are becoming available, including medications, but also other therapies, such as biofeedback for treatment of functional defecation disorders, electrical stimulation, and surgeries. The aim of this article is to provide an update on the medications that are available for management of chronic constipation, especially with the development and study of newer medications, such as Linaclotide and Lubiprostone with promising results in both adult and pediatric patients.

SUMMARY

This review will help us identify and have a better understanding regarding what medications are available for use and the indications, so that we can better manage patients with chronic constipation. VIDEO ABSTRACT.

Chronic constipation and abdominal pain: Independent or closely interrelated symptoms?

Constipation is both a symptom and a disorder, seen in both functional constipation and irritable bowel syndrome with constipation predominance (IBS-C). Despite the Rome IV criteria distinguishing between these conditions, they share many therapeutic approaches. This review aims to explore the relationship between constipation and abdominal pain and assess the evidence surrounding whether laxation improves abdominal pain and whether such a response to laxation differs between IBS-C and functional constipation. In patients with functional constipation, increasing frequency of bowel motions by laxatives regardless of mechanism of action is associated with reductions in the severity of abdominal pain, supporting the role of constipation as a contributor to abdominal discomfort. In patients with IBS-C, evidence from systematic reviews indicates that abdominal pain is driven by factors additional to constipation alone and that visceral analgesic modulation is also needed to optimize pain. Changing definitions of IBS-C and heterogeneity in clinical trial design including endpoints have raised uncertainty about the comparative ability of older laxatives without known neuromodulatory effects to improve chronic abdominal pain compared with new secretagogues and prokinetics for the management of IBS-C. While it is known that abdominal pain is associated with constipation and laxation contributes to relief of that pain, it remains unproven whether proposed visceral analgesic properties of new laxatives provide greater pain relief than laxation alone. However, it is likely that the response to laxation in IBS-C is only part of the puzzle.

European society of neurogastroenterology and motility guidelines on functional constipation in adults

INTRODUCTION

Chronic constipation is a common disorder with a reported prevalence ranging from 3% to 27% in the general population. Several management strategies, including diagnostic tests, empiric treatments, and specific treatments, have been developed. Our aim was to develop European guidelines for the clinical management of constipation.

DESIGN

After a thorough review of the literature by experts in relevant fields, including gastroenterologists, surgeons, general practitioners, radiologists, and experts in gastrointestinal motility testing from various European countries, a Delphi consensus process was used to produce statements and practical algorithms for the management of chronic constipation.

KEY RESULTS

Seventy-three final statements were agreed upon after the Delphi process. The level of evidence for most statements was low or very low. A high level of evidence was agreed only for anorectal manometry as a comprehensive evaluation of anorectal function and for treatment with osmotic laxatives, especially polyethylene glycol, the prokinetic drug prucalopride, secretagogues, such as linaclotide and lubiprostone and PAMORAs for the treatment of opioid-induced constipation. However, the level of agreement between the authors was good for most statements (80% or more of the authors). The greatest disagreement was related to the surgical management of constipation.

CONCLUSIONS AND INFERENCES

European guidelines on chronic constipation, with recommendations and algorithms, were developed by experts. Despite the high level of agreement between the different experts, the level of scientific evidence for most recommendations was low, highlighting the need for future research to increase the evidence and improve treatment outcomes in these patients.

Second Asian Consensus on Irritable Bowel Syndrome

BACKGROUND/AIMS

There has been major progress in our understanding of the irritable bowel syndrome (IBS), and novel treatment classes have emerged. The Rome IV guidelines were published in 2016 and together with the growing body of Asian data on IBS, we felt it is timely to update the Asian IBS Consensus.

METHODS

Key opinion leaders from Asian countries were organized into 4 teams to review 4 themes: symptoms and epidemiology, pathophysiology, diagnosis and investigations, and lifestyle modifications and treatments. The consensus development process was carried out by using a modified Delphi method.

RESULTS

Thirty-seven statements were developed. Asian data substantiate the current global viewpoint that IBS is a disorder of gut-brain interaction. Socio-cultural and environmental factors in Asia appear to influence the greater overlap between IBS and upper gastrointestinal symptoms. New classes of treatments comprising low fermentable oligo-, di-, monosacharides, and polyols diet, probiotics, non-absorbable antibiotics, and secretagogues have good evidence base for their efficacy.

CONCLUSIONS

Our consensus is that all patients with functional gastrointestinal disorders should be evaluated comprehensively with a view to holistic management. Physicians should be encouraged to take a positive attitude to the treatment outcomes for IBS patients.

Canadian Association of Gastroenterology Clinical Practice Guideline for the Management of Irritable Bowel Syndrome (IBS)

BACKGROUND & AIMS

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal (GI) disorders, affecting about 10% of the general population globally. The aim of this consensus was to develop guidelines for the management of IBS.

METHODS

A systematic literature search identified studies on the management of IBS. The quality of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development and Evaluation (GRADE) approach. Statements were developed through an iterative online platform and then finalized and voted on by a multidisciplinary group of clinicians and a patient.

RESULTS

Consensus was reached on 28 of 31 statements. Irritable bowel syndrome is diagnosed based on symptoms; serological testing is suggested to exclude celiac disease, but routine testing for C-reactive protein (CRP), fecal calprotectin or food allergies is not recommended. A trial of a low fermentable oligosaccharides, disaccharides, monosaccharides, polyols (FODMAP) diet is suggested, while a gluten-free diet is not. Psyllium, but not wheat bran, supplementation may help reduce symptoms. Alternative therapies such as peppermint oil and probiotics are suggested, while herbal therapies and acupuncture are not. Cognitive behavioural therapy and hypnotherapy are suggested psychological therapies. Among the suggested or recommended pharmacological therapies are antispasmodics, certain antidepressants, eluxadoline, lubiprostone, and linaclotide. Loperamide, cholestyramine and osmotic laxatives are not recommended for overall IBS symptoms. The nature of the IBS symptoms (diarrhea-predominant or constipation-predominant) should be considered in the choice of pharmacological treatments.

CONCLUSIONS

Patients with IBS may benefit from a multipronged, individualized approach to treatment, including dietary modifications, psychological and pharmacological therapies.

Lubiprostone in the treatment of chronic idiopathic constipation: an update on health-related quality of life and patient-reported outcomes

Chronic idiopathic constipation, if inadequately treated, can be bothersome with a detrimental effect on patients’ quality of life (QOL). This may also result in frequent health care visits, increasing the burden of this ailment’s medical cost. Management strategies, focused on lifestyle changes, include increased exercise, a high-fiber diet, and toilet training. Pharmacologic options include fiber supplementation, laxatives, serotonergic agents, and prosecretory agents such as lubiprostone. In this review, we were able to conclude that lubiprostone, when used for chronic idiopathic constipation, has a significantly beneficial effect on both patients’ symptoms and their QOL. In multiple randomized controlled trials, it has been found to have increased the number of spontaneous bowel movements at different time endpoints. Corresponding improvements were also observed for abdominal bloating, discomfort, stool frequency, and straining symptoms among patients.

Efficacy of Secretagogues in Patients With Irritable Bowel Syndrome With Constipation: Systematic Review and Network Meta-analysis

BACKGROUND & AIMS

Several secretagogues have been approved for the treatment of irritable bowel syndrome with constipation (IBS-C). However, their relative efficacy is unclear because there have been no head-to-head randomized controlled trials. We conducted a network meta-analysis to compare their efficacies in patients with IBS-C.

METHODS

We searched MEDLINE, EMBASE, EMBASE Classic, and the Cochrane Central Register of Controlled Trials through June 2018 to identify randomized controlled trials assessing the efficacy of secretagogues in adults with IBS-C. Trials included in the analysis reported a dichotomous assessment of overall response to therapy, and data were pooled using a random-effects model. Efficacy and safety of secretagogues were reported as a pooled relative risk with 95% confidence interval to summarize the effect of each comparison tested, and treatments were ranked according to their P score.

RESULTS

We identified 15 eligible randomized controlled trials of secretagogues that included 8462 patients. Linaclotide, lubiprostone, plecanatide, and tenapanor were superior to placebo for the treatment of IBS-C. Linaclotide (290 μg once daily) was ranked first in efficacy based on the end point recommended by the Food and Drug Administration for trials in IBS-C, the primary end point used in each trial, abdominal pain, and complete spontaneous bowel movements. Tenapanor (50 mg twice daily) was ranked first for decreasing bloating. Total numbers of adverse events were significantly larger with linaclotide (290 and 500 μg once daily) and plecanatide (3 mg once daily) compared with placebo. However, plecanatide 6 mg once daily ranked first for safety. Diarrhea was significantly more common with all drugs, except lubiprostone (8 μg twice daily). Nausea was significantly more common in patients who received lubiprostone.

CONCLUSIONS

In a network analysis of randomized controlled trials of secretagogues for IBS-C, we found all drugs to be superior to placebo. Efficacy was similar among individual drugs and dosages for most end points. However, data were extracted at the 12-week time point, so the long-term relative efficacy of these drugs is unknown.

Guidelines on the management of irritable bowel syndrome: In memory of Professor Witold Bartnik

These guidelines constitute an update of the previous "Recommendations on the management of irritable bowel syndrome" issued in 2008. They have been developed by a Task Force organized by the Governing Board of the Polish Society of Gastroenterology. They discuss, with particular emphasis on new scientific data covering papers published since 2008, the aetiology, epidemiology, clinical presentation, diagnostic principles and criteria for the diagnosis, and recommendations for the treatment of irritable bowel syndrome (IBS). The English-language acronym for the syndrome (IBS) has become popular in medical and popular scientific language. It is also widely recognized by patients who identify with this diagnosis. Therefore, in the discussed guidelines, this is what we will use.

Chronic abdominal pain in irritable bowel syndrome - current and future therapies

INTRODUCTION

Irritable bowel syndrome (IBS) is a functional gut disorder that typically manifests in early adult years. One of the two major symptoms of the disease is chronic, visceral pain. The patients report pain as the most distressing symptom with the greatest impact on quality of life, challenging both to patients and healthcare providers. Areas covered: This review focuses on the pathophysiology of abdominal pain in IBS and describes current treatment possibilities. It also covers latest findings that may lead to novel pharmacological options in IBS pain management. Expert commentary: Pain is the main contributor to severity in IBS. Seeking pain alleviation is the most common reason that IBS sufferers consult with their physicians. Not all patients report being satisfied with available treatments for pain in IBS and there is a pressing need to find new, more efficient therapies for this syndrome.

Clinical Practice Guidelines for Irritable Bowel Syndrome in Korea, 2017 Revised Edition

In 2011, the Korean Society of Neurogastroenterology and Motility (KSNM) published clinical practice guidelines on the management of irritable bowel syndrome (IBS) based on a systematic review of the literature. The KSNM planned to update the clinical practice guidelines to support primary physicians, reduce the socioeconomic burden of IBS, and reflect advances in the pathophysiology and management of IBS. The present revised version of the guidelines is in continuity with the previous version and targets adults diagnosed with, or suspected to have, IBS. A librarian created a literature search query, and a systematic review was conducted to identify candidate guidelines. Feasible documents were verified based on predetermined inclusion and exclusion criteria. The candidate seed guidelines were fully evaluated by the Guidelines Development Committee using the Appraisal of Guidelines for Research and Evaluation II quality assessment tool. After selecting 7 seed guidelines, the committee prepared evidence summaries to generate data exaction tables. These summaries comprised the 4 main themes of this version of the guidelines: colonoscopy; a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols; probiotics; and rifaximin. To adopt the core recommendations of the guidelines, the Delphi technique (ie, a panel of experts on IBS) was used. To enhance dissemination of the clinical practice guidelines, a Korean version will be made available, and a food calendar for patients with IBS is produced.

Analysis of Nausea in Clinical Studies of Lubiprostone for the Treatment of Constipation Disorders

BACKGROUND

Lubiprostone is a ClC-2 chloride channel activator approved for the treatment of chronic idiopathic constipation (CIC) and opioid-induced constipation (OIC) in adults and irritable bowel syndrome with constipation (IBS-C) in women. Lubiprostone is generally well tolerated, with nausea being the most common adverse event.

AIMS

To characterize nausea with lubiprostone using pooled results from clinical studies in patients with CIC, OIC, or IBS-C.

METHODS

Data from three 3- and 4-week placebo-controlled studies and three long-term open-label studies were pooled for the CIC analysis. The OIC and IBS-C analyses each used pooled data from three 12-week placebo-controlled studies and one 36-week open-label extension study.

RESULTS

The populations included the following numbers of patients: CIC, 316 (placebo) and 1113 (lubiprostone 24 mcg twice daily [BID]); OIC, 652 (placebo) and 889 (lubiprostone 24 mcg BID); and IBS-C, 435 (placebo) and 1011 (lubiprostone 8 mcg BID). The incidence of nausea in lubiprostone-treated patients ranged from 11.4 to 31.1%, with the highest incidence in patients with CIC. Among patients with any nausea, most reported only mild or moderate severity (96.5-99.1% across indications) and only one event (83.6-88.7%); most events occurred within the first 5 days of treatment.

CONCLUSIONS

Nausea was the most common adverse event following the treatment with lubiprostone. Event rates varied by indication and dose, and the majority of nausea adverse events were mild to moderate in severity. Nausea events predominantly occurred early in the treatment period in all of the pooled study populations.

[Pharmacotherapy in Patients with Chronic Constipation]

Chronic constipation is one of the most common digestive diseases frequently observed in a clinical setting. It has been known to cause considerable damage to the quality of life of patients. Despite recent developments, there are considerable limitations in the use of constipation-modulating agents in Korea. Chloride channel inhibitors, such as lubiprostone and linaclotide, have not been introduced in Korea yet, and prucalopride and several kinds of polyethylene glycol are not covered under medical insurance. This article assesses medicines that are clinically available for the management of constipation in Korea, with a brief review of agents that have recently developed around the world.

Luminally Acting Agents for Constipation Treatment: A Review Based on Literatures and Patents

Constipation is one of the most frequently reported gastrointestinal (GI) disorders that negatively impacts quality of life and is associated with a significant economic burden to the patients and society. Traditional treatments including lifestyle modification and laxatives are often ineffective in the more severe forms of constipation and over the long term. New medications targeting at intestinal chloride channels and colonic serotonin receptors have been demonstrated effective in recent years. Emerging agents focusing on improving intestinal secretion and/or colonic motility have been shown effective in animal models and even in clinical trials. Recognization of the role of cystic fibrosis transmembrane regulator (CFTR) and calcium-activated chloride channels (CaCCs) in intestine fluid secretion and motility modulation makes CFTR and CaCCs promising molecule targets for anti-constipation therapy. Although there are multiple choices for constipation treatment, there is still a recognized need for new medications in anti-constipation therapy. The present review covers the discovery of luminally acting agents for constipation treatment described in both patents (2011–present) and scientific literatures.

Dietary and pharmacological treatment of abdominal pain in IBS

This review introduces the principles of visceral sensation and appraises the current approaches to management of visceral pain in functional GI diseases, principally IBS. These approaches include dietary measures including fibre supplementation, low fermentable oligosaccharides, disaccharides, monosaccharides and polyols diet, and pharmacological approaches such as antispasmodics, peppermint oil, antidepressants (tricyclic agents, selective serotonin reuptake inhibitors), 5-HT₃ receptor antagonists (alosetron, ondansetron, ramosetron), non-absorbed antibiotic (rifaximin), secretagogues (lubiprostone, linaclotide), μ-opioid receptor (OR) and κ-OR agonist, δ-OR antagonist (eluxadoline), histamine H1 receptor antagonist (ebastine), neurokinin-2 receptor antagonist (ibodutant) and GABAergic agents (gabapentin and pregabalin). Efficacy and safety are discussed based on pivotal trials or published systematic reviews and meta-analysis, expressing ORs or relative risks and their 95% CIs. Potential new approaches may be based on recent insights on mucosal expression of genes, and microRNA and epigenetic markers in human biopsies and in animal models of visceral hypersensitivity.The objectives of this review are to appraise the physiology and anatomy of gut sensation and the efficacy in the relief of visceral pain (typically in IBS) of several classes of therapies. These include fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) and different classes of medications (box 1). Box 1Classes of pharmacological agents for visceral painAntidepressants (tricyclic agents, selective serotonin reuptake inhibitors)Peppermint oil5-HT₃ receptor antagonists (alosetron, ondansetron, ramosetron)Non-absorbed antibiotic (rifaximin)Secretagogues (lubiprostone, linaclotide)μ-Opioid receptor (OR) and κ-OR agonist and δ-OR antagonist (eluxadoline)Histamine H1 receptor antagonist (ebastine)Neurokinin-2 receptor antagonist (ibodutant)GABAergic agents (gabapentin and pregabalin).

Lubiprostone improves intestinal permeability in humans, a novel therapy for the leaky gut: A prospective randomized pilot study in healthy volunteers

BACKGROUND AND AIMS

The barrier function of the small intestinal mucosa prevents the introduction of undesired pathogens into the body. Breakdown of this barrier function increases intestinal permeability. This has been proposed to induce not only gastrointestinal diseases, including inflammatory bowel disease and irritable bowel syndrome, but also various other diseases, including allergies, diabetes mellitus, liver diseases, and collagen diseases, which are associated with this so called "leaky gut syndrome." As such, a method to prevent leaky gut syndrome would have substantial clinical value. However, no drugs have been demonstrated to improve disturbed intestinal permeability in humans to date. Therefore, we investigated whether a drug used to treat chronic constipation, lubiprostone, was effective for this purpose.

METHODS

Healthy male volunteers were treated with lubiprostone (24 μg/day) for 28 days. Intestinal permeability was evaluated by measuring the lactulose-mannitol ratio (LMR) after administration of diclofenac and compared with an untreated group. The examination was conducted three times in total, i.e., at baseline before diclofenac administration and after 14 and 28 days of lubiprostone treatment. Blood endotoxin activity was also evaluated at the same time points.

RESULTS

The final analysis was conducted on 28 subjects (14 in the lubiprostone group and 14 in the untreated group). The LMR after 28 days of treatment was significantly lower in the lubiprostone group than that in the untreated group (0.017 vs. 0.028, respectively; 95% confidence interval, -0.022--0.0001; p = 0.049). Blood endotoxin activity exhibited almost no change over time in the lubiprostone and untreated groups and displayed no significant differences at any time point of examination.

CONCLUSIONS

This study is the first to report an improvement in leaky gut using an available drug in humans. The result suggests that lubiprostone may prevent and ameliorate "leaky gut syndrome". However, a pivotal trial is needed to confirm our finding.

A Randomized, Double-Blind, Placebo-Controlled Trial to Examine the Effectiveness of Lubiprostone on Constipation Symptoms and Colon Transit Time in Diabetic Patients

OBJECTIVES

Constipation is the most common GI symptom in patients with diabetes mellitus (DM). Importantly, patients with constipation have lower health-related quality of life than those without constipation. Effective therapies for constipation are limited and there is a paucity of data evaluating the treatment of constipation in diabetics.

METHODS

Diabetic patients with chronic idiopathic constipation (CIC) as defined by Rome III criteria were recruited from outpatient clinics at a tertiary-care center and a Veterans Administration Hospital. Demographic data, baseline stool patterns, and a constipation-specific quality of life survey (Patient Assessment of Constipation Quality of Life (PAC-QOL)) were obtained. Baseline colonic transit time (CTT) was evaluated utilizing the wireless motility capsule. Patients were randomized in a double-blind fashion to 48 mcg per day lubiprostone or placebo for 8 weeks. The primary end point measured was the difference in number of spontaneous bowel movements (SBMs) per week vs. baseline for each group at each week after initiation of therapy. Secondary end points included changes in CTT after 4 weeks of therapy, PAC-QOL after 8 weeks of therapy, and changes from baseline in associated gastrointestinal (GI) symptoms as well as need for rescue medication at 2, 4, and 8 weeks.

RESULTS

Seventy-six patients (mean age, 56.9±9.1 years, 62% females) were randomized. There were no significant differences between the two groups' baseline data or demographics. During the 8-week treatment period, patients in the lubiprostone group experienced an average of 1.83±0.80 (P=0.02) more SBMs per week than those in the placebo group as compared with baseline. The duration of CTT at Week 4 was shorter by an average of 13 h compared with baseline in the lubiprostone group, and was prolonged by an average of 7 h compared with baseline in the placebo group, leading to a treatment effect of 20.3±7.3 h (P=0.006). PAC-QOL improved in both the groups; however, there was no significant difference between the groups. There was no difference in associated GI symptoms and need for rescue medication between the two groups after 8 weeks. There were no serious adverse events reported during the study.

CONCLUSIONS

This study suggests that lubiprostone is a safe and effective treatment for increasing weekly SBMs and decreasing CTT in patients with DM and CIC.

Pharmacological treatment for antipsychotic-related constipation

BACKGROUND

Antipsychotic-related constipation is a common and serious adverse effect, especially for people taking clozapine. Clozapine has been shown to impede gastrointestinal motility, leading to constipation, and has been reported in up to 60% of patients receiving clozapine. In rare cases, complications can be fatal. Appropriate laxatives should be prescribed to treat constipation in people taking antipsychotics, but there is a lack of guidance on the comparative effectiveness and harms of different agents in this population. An understanding of the effectiveness and safety of treatment for antipsychotic-related constipation is important for clinicians and patients alike.

OBJECTIVES

To evaluate the effectiveness and safety of pharmacologic treatment (versus placebo or compared against another treatment) for antipsychotic-related constipation (defined as constipated patients of any age, who are treated with antipsychotics, regardless of dose, in which constipation is considered to be an antipsychotic-related side effect).

SEARCH METHODS

We searched the Cochrane Schizophrenia Group's Trials Register (15 June 2015), which is based on regular searches of MEDLINE, Embase, CINAHL, BIOSIS, AMED, PubMed, PsycINFO, and registries of clinical trials, grey literature, and conference proceedings. There are no language, date, document type, or publication status limitations for inclusion of records in this register. We also handsearched bibliographies and contacted relevant authors for additional information.

SELECTION CRITERIA

We included all published and unpublished randomised controlled trials (RCTs) investigating the efficacy of pharmacological treatments in patients with antipsychotic-related constipation. Pharmacological treatments included laxatives and other medicines that could reasonably be used to combat constipation in this population (e.g. anticholinergic agents, like bethanecol).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data from all included studies and assessed trials for risk of bias. A third author reviewed 20% of trials. We analysed dichotomous data using relative risks (RR) and the 95% confidence intervals (CI). We assessed risk of bias for included studies and used GRADE to create a 'Summary of findings' table. We discussed any disagreement, documented decisions, and attempted to contact study authors when necessary.

MAIN RESULTS

We identified two relevant Chinese studies (N = 480) that contributed data to this review. Both studies were over ten years old and poorly reported, lacking descriptions of contemporary CONSORT reporting prerequisites, such as sequence generation, allocation concealment, blinding, participant flow, how the sample size was determined, or how outcomes were measured. The studies also did not report trial registration, pre-specified protocols, consent processes, ethical review, or funding source. We were unsuccessful in making contact with the authors to clarify the missing details. We classified both studies as having an overall high risk of bias.One study compared glycerol suppository with the traditional Chinese medicine (TCM) approaches of tuina massage and acupuncture. Compared to tuina massage, glycerol laxative was less effective in relieving constipation at both two days after treatment (1 RCT; N = 120; RR 2.88, 95% CI 1.89 to 4.39; very low-quality evidence), and three days (1 RCT; N = 120; RR 4.80, CI 1.96 to 11.74, very low-quality evidence). Favourable results were also seen for acupuncture at two days (1 RCT; N = 120; RR 3.50; 95% CI 2.18 to 5.62; very low-quality evidence), and at three days (1 RCT; N = 120; RR 8.00, 95% CI 2.54 to 25.16; very low-quality evidence).The other study compared mannitol, an osmotic laxative, with rhubarb soda or phenolphthalein. Mannitol was more effective than rhubarb soda or phenolphthalein in trelieving constipation within 24 hours of treatment (1 RCT; N = 240; RR 0.07; 95% CI 0.02 to 0.27, very low-quality evidence).No data were reported for our other important outcomes: need for rescue medication, bowel obstruction (a complication of antipsychotic-related constipation), quality of life, adverse events, leaving the study early, and economic costs.

AUTHORS' CONCLUSIONS

We had hoped to find clinically useful evidence appraising the relative merits of the interventions routinely used to manage antipsychotic-related constipation, a common and potentially serious adverse effect of the use of these drugs. The results were disappointing. There were no data comparing the common pharmacological interventions for constipation, such as lactulose, polyethylene glycol, stool softeners, lubricant laxatives, or of novel treatments such as linaclotide. Data available were very poor quality and the trials had a high risk of bias. Data from these biased studies suggested that mannitol, an osmotic laxative, was more effective than rhubarb soda and phenolphthalein in relieving constipation, and a two-week course of glycerol suppositories was less effective than the TCM approaches of tuina massage and acupuncture.Overall, there is insufficient trial-based evidence to assess the effectiveness and safety of pharmacological interventions for treating antipsychotic-related constipation, due to limited, poor quality data (few studies with high risk of bias and no meta-analyses). The methodological limitations in the included studies were obvious, and any conclusions based on their results should be made with caution. Methodologically rigorous RCTs evaluating interventions for treating antipsychotic-related constipation are needed.

Possible Effect of Concomitant Prokinetics and Herbal Medicines against Nausea in Patients Taking Lubiprostone

Background and Aim. Lubiprostone is a novel laxative that sometimes causes nausea, but preventive strategies remain unconfirmed. Methods. We retrospectively chose 126 patients prescribed lubiprostone from 2013 to 2016. Medical records were reviewed to clarify whether nausea developed after administration of the drug. Background characteristics, including concomitant medicines, were also reviewed. Results. The most common adverse symptom was diarrhea (23.8%). Nausea occurred in 16 patients (12.7%). Patients taking either prokinetics or herbal medicines or both were unlikely to develop nausea (p=0.007). Conclusions. Concomitant prokinetics and/or herbal medicines may help alleviate lubiprostone-induced nausea.

Effects of baseline abdominal pain and bloating on response to lubiprostone in patients with irritable bowel syndrome with constipation

BACKGROUND

Lubiprostone (8 μg b.d.) received US Food and Drug Administration (FDA) approval in 2008 for the treatment of constipation-predominant irritable bowel syndrome (IBS-C) in women aged ≥18 years. In 2012, the FDA issued new guidance for IBS-C clinical trials, recommending a composite endpoint incorporating both abdominal pain and stool frequency.

AIM

In a post hoc analysis, similar criteria were applied to data from two pivotal, phase 3, double-blind, randomised trials of lubiprostone in patients with IBS-C.

METHODS

Included patients had a baseline spontaneous bowel movement (SBM) frequency <3/week and abdominal pain or bloating ratings ≥1.36 on a 5-point scale [0 (absent) to 4 (very severe)]. Responders (composite endpoint) had a mean pain reduction ≥30% compared with baseline, and an increase from baseline of ≥1 SBM/week for ≥6 of the 12 treatment weeks. Lubiprostone effects on abdominal pain alone were also evaluated, as were bloating alone and in a composite endpoint with stool frequency.

RESULTS

In pooled data, 325 patients received lubiprostone and 180 received placebo. Rates of response were higher with lubiprostone vs. placebo for the composite endpoint of improved pain and stool frequency (26.3% vs. 15.3%, respectively; P = 0.008) and the composite endpoint of improved bloating and stool frequency (23.8% vs. 12.6%, respectively; P = 0.012). Response rates were also higher with lubiprostone vs. placebo for abdominal pain alone (P = 0.005) and bloating alone (P = 0.012).

CONCLUSION

Lubiprostone was significantly more effective than placebo in improving abdominal pain or bloating, and also in composite endpoints that included stool frequency.

Childhood constipation: finally something is moving!

Recent developments in the evaluation and treatment of childhood constipation are likely to influence the way we deal with pediatric defecation disorders in the near future. Innovations in both colonic and anorectal manometry are leading to novel insights into functional defecation disorders in children. Promising results have been achieved with innovative therapies such as electrical stimulation and new drugs with targets that differ from conventional pharmacological treatments. Also, new surgical approaches, guided by manometric findings, have led to improvement in patient outcome. Finally, utilization of non-pharmacological interventions such as fiber and probiotics has been a field of particular interest in recent years. The aim of this article is to provide an update on these and other novel diagnostic and therapeutic tools related to childhood constipation.

Progress in treatment of irritable bowel syndrome

Irritable bowel syndrome is a common functional bowel disorder whose incidence has a tendency to increase year by year. At present, the pathogenesis of irritable bowel syndrome is not completely clear, and treatments are mainly symptomatic. In recent years, with the better understanding of its pathogenesis, some new drugs and treatments have been developed, such as methods of improving intestinal micro-ecology (antibiotics, fecal transplantation), mesalazine, and new drugs of improving intestinal secretion, motiligy and sensitivity, plant drugs, some of which have been applied clinically. This article will make a review of the current progress in treatment of irritable bowel syndrome.

Persistent constipation and abdominal adverse events with newer treatments for constipation

Background

Clinical trials of several new treatments for opioid-induced constipation (OIC), chronic idiopathic constipation (CIC) and constipation-predominant irritable bowel syndrome (IBS-C) have focused on differences between subjects relieved of constipation with placebo and active treatment. Patients and clinicians however, are more interested in the probability these treatments provide actual relief of constipation and its associated symptoms.

Methods

We searched the medical literature using MEDLINE and Cochrane central register of controlled trials. Randomised, placebo-controlled trials that examined the use of methylnaltrexone, naloxegol, lubiprostone, prucalopride or linaclotide in adults with OIC, CIC and IBS-C were eligible for inclusion. The primary efficacy measure was relief of constipation. Adverse event data for abdominal symptoms were also analysed.

Key results and findings

25 publications were included in our analyses. The proportion of constipated individuals with active treatment was significantly lower than the proportion with placebo; however, in 15 of these 20 trials analysed, a majority of patients remained constipated with active treatment. Analyses of adverse event data revealed that the percentage of participants who experienced abdominal pain, diarrhoea and flatulence with active treatment was higher than that with placebo in the majority of trials analysed.

Conclusions

Newer pharmacological treatments for constipation are superior to placebo in relieving constipation, but many patients receiving active treatment may remain constipated. In addition, all 5 of the treatments studied are accompanied by no change or a possible increase in the prevalence of abdominal symptoms, such as abdominal pain, diarrhoea and flatulence.

Lubiprostone Is Effective in the Treatment of Chronic Idiopathic Constipation and Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To evaluate the efficacy and safety of lubiprostone in the treatment of chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (IBS-C).

PATIENTS AND METHODS

We performed a literature search of the MEDLINE, Cochrane, Google Scholar, and ClinicalTrials.gov databases (from January 1, 2005, through January 31, 2015). Relevant studies meeting the inclusion criteria were manually searched by 2 independent reviewers. Efficacy outcomes evaluated at 1 week, 1 month, and 3 months of intervention were weekly frequency of spontaneous bowel movements, severity of constipation, consistency of stools, degree of abdominal pain/discomfort, degree of straining, and abdominal bloating.

RESULTS

Of 246 studies identified, data from 9 trials comprising 1468 patients (63.6%) in the lubiprostone group and 841 (36.4%) in the placebo group were analyzed. We found that lubiprostone treatment significantly improved the severity of constipation, stool consistency, abdominal pain, degree of straining, and abdominal bloating at 1 week (P≤.03) and 1 month (P≤.004), except for abdominal pain at 1 month, which was similar to that when treated with placebo (P=.21). At 3 months, except for abdominal bloating (P=.03), there was no difference between lubiprostone and placebo groups in all other outcomes (P≥.05). Adverse effects such as nausea, vomiting, and diarrhea were common (incidence rate, 2.4%-75%); however, the incidence of serious adverse effects was low (<5%) and was mostly unrelated to lubiprostone treatment.

CONCLUSION

Lubiprostone is a safe and efficacious drug for the treatment of chronic idiopathic constipation and irritable bowel syndrome with constipation, with limited adverse effects in 3 months of follow-up.

[Current issues on the treatment of chronic constipation]

Chronic constipation is a very common clinical problem with its prevalence of up to 14% in the general population. It is not a life-threatening disease, but since patient's satisfaction to the treatment is known to be as low as 50%, chronic constipation still remains a clinically challenging problem. Fortunately, many new treatments have been introduced or are to be introduced in the near future. This article will review the basic concepts and the results of recent studies on the new treatments for chronic constipation.

Pharmacological, Pharmacokinetic, and Pharmacogenomic Aspects of Functional Gastrointestinal Disorders

This article reviews medications commonly used for the treatment of patients with functional gastrointestinal disorders. Specifically, we review the animal models that have been validated for the study of drug effects on sensation and motility; the preclinical pharmacology, pharmacokinetics, and toxicology usually required for introduction of new drugs; the biomarkers that are validated for studies of sensation and motility endpoints with experimental medications in humans; the pharmacogenomics applied to these medications and their relevance to the FGIDs; and the pharmacology of agents that are applied or have potential for the treatment of FGIDs, including psychopharmacologic drugs.

Opioid-induced constipation in chronic noncancer pain

PURPOSE OF REVIEW

Opioid-based management of noncancer pain has become much more prevalent over the last 2 decades and is responsible for a wide range of side-effects, particularly affecting the intestinal tract causing opioid-induced constipation (OIC). This review will consider results of recent clinical trials that have provided evidence of new pharmacological management options for the treatment of OIC.

RECENT FINDINGS

Supportive use of conventional agents, such as stool softeners, osmotic laxatives, and stimulating laxatives in OIC has limited efficacy. The peripheral μ-opioid receptor antagonist (PAMORA) methylnaltrexone (MNTX) was first FDA approved for OIC in patients with advanced illness and later also for OIC in noncancer pain patients; clinical trial results indicated MNTX did not reverse opioid analgesia and did not trigger central opioid withdrawal. Another PAMORA, the orally available naloxegol, has also gained recent FDA approval for the treatment of OIC in adults with chronic, noncancer pain. Lubiprostone, a bicyclical fatty acid acting via activation of intestinal chloride channel-2 (ClC-2), was also approved for OIC treatment in patients with noncancer pain.

SUMMARY

PAMORA MNTX and naloxegol and the intestinal chloride channel-2 (ClC-2) activator lubiprostone represent additional possible therapeutic options for the management of OIC in patients with chronic noncancer pain.

Effective Constipation Treatment Changes More Than Bowel Frequency: A Systematic Review and Meta-Analysis

BACKGROUND/AIMS

The marketing of newer agents for treatment of constipation and irritable bowel syndrome with constipation (IBS-C) emphasize improvements in abdominal pain. However, it is not clear whether this observation reflects a unique visceral analgesic effect of these agents or is a general feature of effective laxation. We sought to determine the relationship between improvements in bowel frequency and decreases in abdominal pain in clinical trials of patients with constipation or IBS-C.

METHODS

We searched "PubMed" and "Embase" databanks for clinical trials in patients with constipation or IBS-C, targeting publications that provided detailed data on bowel movement frequency and pain intensity before and after an intervention. We abstracted the results and performed meta-analytic and meta-regression analyses.

RESULTS

Twenty-seven trials (16 constipation and 11 IBS) met entry criteria. Baseline weekly bowel movement frequency was low with 2.35 (2.07-2.64) with differences between constipation (2.00 [1.62-2.38]) and IBS-C (2.77 [2.40-3.14]; Q = 8.18; P = 0.002). Studies reported moderate pain levels (2.12 [1.81-2.42]) with comparable baseline levels in constipation (2.02 [1.63-2.42]) and IBS-C (2.35 [2.10-2.60]; Q = 1.92; P = 0.167). Treatments increased bowel frequency by 2.17 [1.88-2.47] and lowered pain ratings by 0.58 [0.49-0.68]. Meta-regression demonstrated a significant correlation between treatment-induced increases in bowel frequency and decreased pain ratings.

CONCLUSIONS

Our analysis suggests that reduction of abdominal pain observed in clinical trials of constipation and IBS-C is associated with laxation, and may not require specific drug mechanisms, thus arguing against a unique advantage of newer agents over traditional laxatives in the treatment of constipation and IBS-C.

Extracts from peppermint leaves, lemon balm leaves and in particular angelica roots mimic the pro-secretory action of the herbal preparation STW 5 in the human intestine

AIM

The herbal preparation STW 5 contains fresh plant extracts from bitter candytuft whole plant, extracts from greater celandine herb, angelica root, lemon balm leaves, peppermint leaves, caraway fruit, liquorice root, chamomile flower and milk thistle fruit. We recently reported that STW 5 increased intestinal chloride secretion and proposed that this action may be involved in its clinical efficacy in the treatment of irritable bowel syndrome. The aim of this study was to identify the extracts responsible for the secretory action in order to provide the basis to develop novel target oriented herbal combinations.

METHODS

We used the Ussing chamber voltage clamp technique to study the effects of individual extracts of STW 5 on short circuit current (Isc, reflecting electrogenic ion transport across epithelial cells) in mucosal/submucosal preparations of human small or large intestinal specimens and the human epithelial cell line T84.

RESULTS

STW 5 at concentrations of 512 µg/ml and 5120 µg/ml evoked an increase in Isc. The increase at the lower concentration was due to pro-secretory effects of angelica which were nerve mediated. The increase at the higher concentration was additionally mimicked by peppermint and lemon balm. The remaining extracts did not influence ISC in the large intestine. The results were similar in T84 cells except that angelica had no effect while chamomile induced secretion. These pro-secretory effects were reduced by adenylate cyclase inhibitor MDL-12330A, cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor CFTRinh-172 and calcium activated chloride channels blocker 4-acetamido-4-isothiocyanatostilbene-2,2-disulphonic acid (SITS). Liquorice decreased ISC only in small intestine which was reversed by the epithelial sodium channel blocker amiloride.

CONCLUSIONS

Results suggested that the pro-secretory action of STW 5 is mainly due to angelica with lesser contribution of peppermint and lemon balm. Their effects involve activation of cAMP- and Ca(++)-activated Cl(-) channels. We suggest that peppermint, lemon balm and in particular angelica may be the basis to develop novel herbal preparations to specifically treat secretory disorder based on impaired epithelial secretion, such as constipation.

Recent Updates on the Treatment of Constipation

The treatment of constipation aims to regulate the frequency and quantity of stool in order to promote successful defecation. Numerous studies on pharmacologic treatments and non-pharmacologic therapies for constipation have attempted to overcome limitations such as temporary and insufficient efficacy. Conventional laxatives have less adverse effects and are inexpensive, but often have limited efficacy. Recently developed enterokinetic agents and intestinal secretagogues have received attention owing to their high efficacies and low incidences of adverse events. Studies on biofeedback and surgical treatment have focused on improving symptoms as well as quality of life for patients with refractory constipation.