Misoprostol is effective treatment for patients with severe chronic constipation

Exploring Pharmacological Treatments for Chronic Idiopathic Constipation in Adults: A Look Back to the Future

Despite great progress in pharmaceutical research, the medical treatment of chronic idiopathic constipation is far from ideal. The aim of the present article was to review literature data, focusing on poorly studied or commercially unavailable/unapproved drugs potentially useful for the treatment of chronic idiopathic constipation in adults. An extensive online literature search was conducted using the keywords "chronic constipation", "colon", "constipation", "drugs", "laxatives", and "treatment", in various combinations between January 1960 and December 2022. The literature search showed the presence of some drugs whose efficacy has only recently been demonstrated by modern investigations, and which are likely to be incorporated into future guidelines, of others that are proven effective and potentially effective on constipated patients but limited by small or relatively old studies, or by side effects which could be used in experienced hands, and of others that might be useful but lack a solid scientific background. Looking into the future for patients with chronic constipation might add some more tools to the therapeutic portfolio, especially for certain subgroups of these patients.

Chronic Idiopathic Constipation in Adults: A Review on Current Guidelines and Emerging Treatment Options

Chronic idiopathic constipation (CIC) is a common functional bowel disorder characterized by difficult, infrequent, and/or incomplete defecation. It has a great impact on the quality of life and on health care system and represents a heavy economic burden. The diagnosis is based on symptoms, classified by the Rome IV criteria. The aim of this review was to evaluate the current therapeutic guidelines for adult CIC and highlight new emerging treatments. In detail, European, French, Spanish and Korean guidelines have been identified and compared. Osmotic laxatives, and in particular polyethylene glycol, represent the first-line therapeutic approach. Stimulant laxatives are recommended as a second-line therapy. Pelvic floor rehabilitation is recommended in patients with ano-rectal dyssynergia. In patients who fail to improve with pharmacological therapies sacral nerve stimulation is considered as last chance before surgery. Surgical approach has however limited indications in selected cases. Inertia coli refractory to any approach and obstructed defecation are two subtypes which can benefit from surgery. Among emerging agents, prucalopride, a prokinetic agent, is recommended as a second-line treatment in refractory CIC patients. In addition, the secretagogues linaclotide and plecanatide and the bile acid transported inhibitor elobixibat can be effective in patients not responsive to a second-line therapeutic regimen, although they are not worldwide commercially available.

Heterogeneous outcome reporting in adult slow-transit constipation studies: Systematic review towards a core outcome set

BACKGROUND AND AIM

Standardizing evaluative outcomes and their assessment facilitates comparisons between clinical studies and provides a basis for comparing direct effects of different treatment options. The aim of this study was to systematically review types of outcomes and measurement instruments used in studies regarding treatment options for slow-transit constipation (STC) in adults.

METHODS

In this systematic review of the literature, we searched MEDLINE, Embase, and PsycINFO from inception through February 2018, for papers assessing any STC treatment in adult patients. Outcomes were systematically extracted and categorized in domains using the conceptual framework of the Outcome Measures in Rheumatology filter 2.0. Outcome reporting was stratified by decade of publication, intervention, and study type.

RESULTS

Forty-seven studies were included in this systematic review. Fifty-nine different types of outcomes were identified. The outcomes were structured in three core areas and 18 domains. The most commonly reported domains were defecation functions (94%), gastrointestinal transit (53%), and health-care service use (51%). The most frequently reported outcomes were defecation frequency (83%), health-related quality of life (43%), and adverse events and complications (43%). In 62% of the studies, no primary outcome was defined, whereas in two studies, more than one primary outcomes were selected. A wide diversity of measurement instruments was used to assess the reported outcomes.

CONCLUSION

Outcomes reported in studies on STC in adults are heterogeneous. A lack of standardization complicates comparisons between studies. Developing a core outcome set for STC in adults could contribute to standardization of outcome reporting in (future) studies.

Refractory Constipation: What is the Clinician to Do?

Most clinicians will agree that chronic constipation is characterized by abnormal bowel movement consistency and/or frequency plus or minus evacuation symptoms, but patient perception of constipation varies widely and includes symptoms that may or may not meet official defining criteria. Although intermittent constipation is extremely common, only a small minority of patients seek care for their symptoms. Among these patients, dissatisfaction with the currently available laxative options is not uncommon, and many patients will require specialized care for severe or refractory symptoms-especially those with abdominal pain, irritable bowel syndrome overlap, bloating or distention, and psychological comorbidities. This review outlines a physiological assessment of the patient with refractory constipation, exploring treatment options among patients with slow transit, rectal evacuation disorders, and normal transit. In addition, we explore nonlaxative approaches to normal-transit patients bothered by ongoing symptoms, with an emphasis on the biopsychosocial model of functional gastrointestinal disease and treatment of visceral hypersensitivity using neuromodulators. Finally, we propose a comprehensive evaluation algorithm for the management of patients with refractory slow-transit constipation considering surgery and examine surgical options including colectomy and cecostomy using an antegrade continent enema.

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.

Opioid-induced bowel dysfunction: epidemiology, pathophysiology, diagnosis, and initial therapeutic approach

Opioids affect motor and sensory function throughout the gastrointestinal tract, and are frequently associated with a number of gastrointestinal symptoms including constipation, which impairs the quality of life and may limit the dose of opioid or result in discontinuation altogether. Patients with opioid-induced constipation should be assessed by careful history and physical examination, and in some cases where the diagnosis is unclear with select diagnostic tests. Few clinical studies have been conducted to assess the efficacy of various treatments. However, it is generally recommended that first-line therapy begin with opioid rotation, as well as with low-cost and low-risk approaches such as lifestyle changes, consumption of fiber-rich food, stool softeners, and laxatives.

Current developments in pharmacological therapeutics for chronic constipation

Chronic constipation is a common gastrointestinal disease severely affecting the patient׳s quality of life. The traditional treatment of constipation is the use of laxatives. Recently, several new drugs including lubiprostone, linaclotide and prucalopride have been approved for treatment of chronic constipation. However, a significant unmet medical need still remains, particularly among those patients achieving poor results by current therapies. The 5-HT4 receptor modulators velusetrag and naronapride, the guanylate cyclase C agonist plecanatide and the ileal bile acid transporter inhibitor elobixibat are recognized as the most promising drugs under investigation. Herein, we give a comprehensive review on the pharmacological therapeutics for the treatment of chronic constipation, with the purpose of reflecting the drug development trends in this field.

Epidemiology and management of chronic constipation in elderly patients

Constipation is a common functional gastrointestinal disorder, with prevalence in the general population of approximately 20%. In the elderly population the incidence of constipation is higher compared to the younger population, with elderly females suffering more often from severe constipation. Treatment options for chronic constipation (CC) include stool softeners, fiber supplements, osmotic and stimulant laxatives, and the secretagogues lubiprostone and linaclotide. Understanding the underlying etiology of CC is necessary to determine the most appropriate therapeutic option. Therefore, it is important to distinguish from pelvic floor dysfunction (PFD), slow and normal transit constipation. Evaluation of a patient with CC includes basic blood work, rectal examination, and appropriate testing to evaluate for PFD and slow transit constipation when indicated. Pelvic floor rehabilitation or biofeedback is the treatment of choice for PFD, and its efficacy has been proven in clinical trials. Surgery is rarely indicated in CC and can only be considered in cases of slow transit constipation when PFD has been properly excluded. Other treatment options such as sacral nerve stimulation seem to be helpful in patients with urinary dysfunction. Botulinum toxin injection for PFD cannot be recommended at this time with the available evidence. CC in the elderly is common, and it has a significant impact on quality of life and the use of health care resources. In the elderly, it is imperative to identify the etiology of CC, and treatment should be based on the patient’s overall clinical status and capabilities.

Agents that act luminally to treat diarrhoea and constipation

Diarrhoea and constipation are common clinical complaints that negatively affect quality of life, reduce work productivity and lead to considerable health-care expenditure. A variety of therapies have been used to treat these conditions. Unlike drugs that require systemic absorption to exert their effects, luminally acting agents improve diarrhoea and constipation by altering intestinal and/or colonic motility, as well as mucosal absorption and secretion, through a variety of mechanisms. Examples of luminally acting agents for diarrhoea include peripherally acting opiate analogues, enkephalinase inhibitors, bile-acid binding agents, nonabsorbed antibiotics, probiotics, bismuth-containing compounds, berberine and agents with possible effects on intestinal secretion or permeability. Luminally acting drugs for constipation include bulking agents, surfactants, osmotics, stimulants, chloride-channel activators, probiotics, drugs that increase delivery of bile acids to the colon and natural therapies such as prunes and hemp seed extract. As the physiological effects of luminally acting drugs are largely confined to the gastrointestinal tract, these agents are unlikely to cause adverse effects outside of the gastrointestinal tract.

Non-motor extranigral signs and symptoms in Parkinson's disease

Clinical symptoms in Parkinson's disease (PD) comprise both motor and non-motor symptoms. In this disease, synucleinopathic-induced, nigral dopamine deficiency-related dysfunction of the basal ganglia is held responsible for the characteristic levodopa-responsive motor signs and symptoms (bradykinesia, hypokinesia, rigidity), known as parkinsonism and essential for clinical diagnosis in PD, as well as subtle motivational and cognitive dysfunctions. Some motor symptoms, such as tremor and postural instability, and most non-motor symptoms, however, are not fully levodopa-responsive, and suggested to manifest extranigral pathology. These symptoms include autonomic, sleep, sensory and neuropsychiatric symptoms, which in some cases may precede the first signs of motor parkinsonism, closely correlating with the progression of Lewy body pathology in PD. The recognition and treatment of these mostly under-recognized and under-treated symptoms is important, as these symptoms might have more impact on the quality of life in PD patients as compared to motor parkinsonism. On top of this, recognition of these manifestations in the prodromal phase of motor PD is critical to early diagnosis and treatment, as disease-modifying drugs, once identified, should be initiated as soon as possible, preferably in this premotor phase of the disease. On top of this, (non)motor extranigral symptoms in PD might also be of iatrogenic origin, whether directly as indirectly. During conventional, oral, dopaminomimetic treatment, the progressive loss of striatal dopaminergic nerve endings with the loss of cerebral dopamine storage capacity, renders the cerebral dopamine level fully dependent of the plasma levodopa levels, thus changing dopaminergic receptor stimulation from continuous to a more pulsatile pattern. Supposedly due to this process, neuroplastic changes in (sub)cortical dopaminergic pathways might cause therapeutic response fluctuations: motor and nonmotor fluctuations with anxiety- and panic-attacks and/or mood swings, dyskinesias and punding. Finally, dopaminomimetic pharmacotherapy may also induce extranigral non-motor drug-related direct adverse effects, such as impulse control disorders. In this article, non-motor signs and symptoms of extranigral PD-related pathology will be discussed, as well as the (suggested) criteria for diagnosis and treatment. Of course, also the recognition of the signs and symptoms of the prodromal (premotor) phase, suggestive for the presence of the PD, will be discussed. Iatrogenic non-motor symptoms, though, will not be further discussed.

Colchicine is effective for short-term treatment of slow transit constipation: a double-blind placebo-controlled clinical trial

PURPOSE

Although colchicine has been tested in clinical trials for treatment of constipation, the index groups in those trials were composed of special patient groups with developmental neuromuscular defects or failed surgical management. The aim of this study is to investigate the efficacy of colchicine in patients with refractory slow transit constipation.

MATERIALS AND METHODS

Sixty patients with chief complaint of chronic constipation due to slow transit consented to be included in the double-blind placebo-controlled clinical trial. These patients were randomly divided into two groups (each containing 30 patients) to receive either colchicine, 1 mg QD, (group A) or placebo (group B) for 2 months. At the end of the study, Knowles-Eccersly-Scot symptom (KESS, a valid technique to assist in the diagnosis and evaluation of symptoms in constipation) scores were compared between the case and control groups.

RESULTS

The mean KESS score measured at the end of 2 months was 11.67 +/- 3.91 for colchicine and 18.66 +/- 3.72 for placebo group (p = 0.0001).

CONCLUSION

This trial shows that low-dose colchicine is effective in treatment of slow transit constipation.

Chronic constipation in the elderly

Chronic constipation is a common problem in the elderly, with a variety of causes, including pelvic floor dysfunction, medication effects, and numerous age-specific conditions. A stepwise diagnostic and therapeutic approach to patients with chronic constipation based on historical and physical examination features is recommended. Prudent use of fiber supplements and laxative agents may be helpful for many patients. Based on their capabilities, patients with pelvic floor dysfunction should be considered for pelvic floor rehabilitation (biofeedback), although efficacy in the elderly is uncertain. Clinical awareness and focused testing to identify the physiologic abnormalities underlying constipation, while being mindful of situations unique to the elderly, facilitate management, and improve patient outcomes.

Management of chronic constipation in the elderly

Constipation is a significant healthcare problem in the elderly. However, while undoubtedly common in the elderly, data on the prevalence of constipation in general and of its subtypes vary considerably, depending on the nature of the study population and their location. Furthermore, the complexity of the pathophysiology of constipation in this age group is little appreciated. Assumptions regarding 'age-related changes in colorectal physiology' are, for the most part, not supported by scientific evidence and may serve to distract the clinician from uncovering the contributions of co-morbid diseases and the impact of iatrogenic factors. The evidence base from which one can develop recommendations on the management of constipation in the elderly is, for the most part, slim. This becomes most starkly apparent when one attempts to critically assess specific approaches to management. There is insufficient evidence to support the use of many commonly used laxatives both in the general population and in the elderly. Lifestyle interventions have value for some patients but data are lacking on the benefits of these interventions for patients with chronic constipation. Data in the elderly do not exist for most new pharmacological approaches to constipation. Pending the availability of good data, management of constipation in the elderly should be tailored to each individual's needs and expectations, regardless of age or place of residence. In certain situations, constipation may be complicated by the development of impaction; preventive strategies are important in this context. We urge enrolment of many more elderly individuals with chronic constipation in clinical trials designed to address their particular needs.

Opioid-induced bowel dysfunction

Opioid-induced bowel dysfunction is a distressing condition that may persist indefinitely in the clinical setting. As we understand more about normal gastrointestinal (GI) physiology, we are also beginning to understand more fully how opioids cause bowel dysfunction. Current therapeutic interventions for opioid-induced bowel dysfunction can be burdensome and sometimes lack efficacy. Systemic opioid antagonists administered orally can induce laxation, but can unpredictably induce systemic or local GI tract withdrawal symptoms. Two new investigational agents, alvimopan and methylnaltrexone, are peripherally acting opioid antagonists that do not cross the blood-brain barrier. Studies to date show promise that these agents may relieve opioid-induced bowel dysfunction in a well-tolerated manner without reversing central analgesia.

Does postoperative misoprostol use induce intestinal motility? A prospective randomised double-blind trial

BACKGROUND

Misoprostol has been shown to increase colonic activity and decrease colonic transit time in chronic constipation patients.

AIMS

The aim of this prospective, randomised, double-blind study was to examine the effectiveness of rectally administered misoprostol on inducing intestinal motility after gynaecological surgery.

METHODS

Eighty women who underwent hysterectomy were divided randomly into three groups. Group A received misoprostol 200 microg rectally while group B received 400 microg rectal misoprostol after surgery before leaving the operating room. Patients in group C received no drugs. Bowel sounds in four quadrants were checked every hour and possible side-effects of misoprostol like nausea, vomiting, and distension were evaluated. The time interval between surgery and flatus pass and the need of analgesics were noted. Statistical analyses were done with Mann-Whitney U-test and chi2 tests where available.

RESULTS

The time between surgery and presence of bowel sounds in four quadrants were similar in all groups (2.7 +/- 1.6, 2.9 +/- 1.2, 2.8 +/- 1.3 h, for groups A, B, and C, respectively). No difference was observed in flatus pass time. The incidence of nausea was significantly increased in group B compared to controls (P < 0.01). Additional analgesic need was significantly higher in groups A and B when compared to controls (P < 0.05 and P < 0.01, for groups A and B, respectively).

CONCLUSION

Rectally administered misoprostol does not improve intestinal motility in the early postoperative period and thus, it is not effective in providing early oral food intake. On the contrary, it causes distention that requires additional analgesics and vomiting that naturally limits oral diet intake.

Childhood and adolescent constipation: Review and advances in management

Constipation is a common symptom throughout all ages in the pediatric population, both sexes, and all educational and socioeconomic levels. It is estimated that 12% to 30% of the general population suffers from functional constipation. A practical overview of pathogenic mechanisms contributing to constipation is presented, with emphasis on evaluation and management options available to the treating practitioner. The evaluation of constipation requires careful history taking and interpretation. Diagnostic tests such as manometry and colonic scintigraphy are reserved for those severely affected. Constipation can be challenging to treat, especially if pain and discomfort are predominant features. Therapy requires early recognition of the problem; support by physicians and family members; identification and explanation of contributing factors; and the providing of medications, including osmotic and/or stimulant laxatives. When constipation becomes refractory to standard medical treatment, more novel considerations may include probiotics, botulinum toxin, mind-body interventions, electrical stimulation of the intestine, and surgery.

Constipation

Chronic constipation is a common disorder manifested by a variety of symptoms. Assessments of colonic transit and anorectal functions are used to categorize constipated patients into three groups, i.e., normal transit or irritable bowel syndrome, pelvic floor dysfunction (i.e., functional defaecatory disorders) and slow transit constipation. 'Slow transit' constipation is a clinical syndrome attributed to ineffective colonic propulsion and/or increased resistance to propagation of colonic contents. Defaecatory disorders are caused by insufficient relaxation of the pelvic floor muscles or a failure to generate adequate propulsive forces during defaecation. Colonic transit is often delayed in patients with functional defaecatory disorders. Normal and slow transit constipation are generally managed with medications; surgery is necessary for a minority of patients with slow transit constipation. Functional defaecatory disorders are primarily treated with pelvic floor retraining using biofeedback therapy.

Cancer-related constipation

Cancer-related constipation is common and a significant detractor from patient quality of life. It has many possible causes and is still not well understood. Information is lacking on therapies for cancer-related constipation among current medications approved by the US Food and Drug Administration (FDA). Most agents have only been formally tested in comparison with placebo in chronic idiopathic constipation if at all. Few comparative studies of laxatives have been performed to establish superiority or synergy. As we understand more about the physiology of the gastrointestinal tract, new targeted therapies have become available. These include a selective chloride channel activator, lubiprostone, and a selective 5HT4 serotonin receptor agonist, tegaserod, both of which have been FDA approved for chronic idiopathic constipation. The role of these agents in cancer-related constipation remains to be seen. On the horizon are two investigational peripherally acting opioid receptor antagonists, alvimopan and methylnaltrexone. Preliminary results in cancer-related constipation suggest that these agents may be important additions to our treatment repertoire.

Efficacy and safety of traditional medical therapies for chronic constipation: systematic review

OBJECTIVES

Constipation is common, and its treatment is unsatisfactory. Although many agents have been tried, there are limited data to support their use. Our aim was to undertake a systematic review of the efficacy and safety of traditional medical therapies for chronic constipation and to make evidence-based recommendations.

METHODS

We searched the English literature for drug trials evaluating treatment of constipation by using MEDLINE and PUBMED databases from 1966 to 2003. Only studies that were randomized, conducted on adult subjects, and published as full manuscripts were included. Studies were assigned a quality score based on published methodology. Standard forms were used to abstract data regarding study design, duration, outcome measures, and adverse events. By using the cumulative evidence of published data for each agent, recommendations were made regarding their use following the United States Preventive Services Task Force guidelines.

RESULTS

Good evidence (Grade A) was found to support the use of polyethylene glycol (PEG) and tegaserod. Moderate evidence (Grade B) was found to support the use of psyllium, and lactulose. There was a paucity of quality data regarding many commonly used agents including milk of magnesia, senna, bisacodyl, and stool softeners.

CONCLUSIONS

There is good evidence to support the use of PEG, tegaserod, lactulose, and psyllium. Surprisingly, there is a paucity of trials for many commonly used agents. These aspects should be considered when designing trials comparing new agents with traditional therapies because their use may not be well validated.

The treatment of chronic constipation in elderly people: an update

Constipation is a common problem in elderly persons, with prevalence ranging from 15% to 20% in the community-dwelling elderly population and up to 50% in some studies of nursing home residents. In these patients, constipation results from a combination of risk factors, such as reduced fibre and fluid intake, decreased physical activity resulting from chronic diseases and multiple medications. Despite the high prevalence of constipation, there is surprisingly little evidence available on which to base management decisions of this common condition. Increased fluid intake, regular physical activity and high fibre intake are usually proposed as first step nonpharmacological measures. However, adherence to these measures is limited and pharmacological treatment is frequently required. Data are too limited, especially in elderly persons, to formally recommend one class of laxatives over another or one agent over another within each class. However, bulk-forming and osmotic laxatives are usually recommended as first-line agents, even though data on their effectiveness are limited. The need to maintain good hydration is a limitation in the use of bulk-forming laxatives, in particular, in frail elderly patients. In these patients, polyethylene glycol, an osmotic agent, is an attractive alternative. In addition, it has been shown to relieve faecal impaction in frail patients with neurological disease. Its cost and potential danger in patients at high risk for aspiration is, however, a limitation. Stimulant laxatives are considered mainly as an intermittent treatment in patients who do not respond to bulk-forming or osmotic laxatives. Several promising compounds such as the new serotonin 5-HT4 receptor agonists (tegaserod, prucalopride) and neurotrophin-3 (NT3) have not been adequately tested in older individuals. They are not routinely used and their role in the management of constipation in these patients will be more precisely defined in the future. Other treatment options are available (acupuncture, biofeedback, botulinum toxin and surgery), but experience with these interventions in elderly patients is limited and their indications in this population remain to be clarified. Management of constipation in elderly persons depends largely on experience and beliefs. Several new compounds seem promising but will need to be specifically tested in this population before being recommended.

Treatment of Severe and Intractable Constipation

A careful clinical evaluation, exclusion of secondary causes (eg, colonic obstruction, metabolic conditions, and drug-induced constipation), and assessments of colonic transit and rectal evacuation are necessary to ascertain whether constipation is attributable to normal colonic transit, delayed colonic transit (ie, slow-transit constipation), or a rectal evacuation disorder (with or without delayed colonic transit). Idiopathic slow-transit constipation is a clinical syndrome predominantly affecting women and is characterized by intractable constipation and delayed colonic transit. This syndrome is attributed to disordered colonic motor function and spans a spectrum of variable severity ranging from patients who have relatively mild delays in transit, but are otherwise indistinguishable from irritable bowel syndrome, at one extreme to patients with colonic inertia or chronic megacolon at the other extreme. Most patients are treated with one or more pharmacological agent. A subtotal colectomy is effective and occasionally indicated for patients with medically refractory severe slow-transit constipation, provided that pelvic floor dysfunction has been excluded or treated. Pelvic floor dysfunction can be diagnosed by the clinical features and anorectal testing. Most patients with pelvic floor dysfunction will respond to pelvic floor retraining by biofeedback therapy.

Treatment of chronic constipation with colchicine: randomized, double-blind, placebo-controlled, crossover trial

OBJECTIVE

Refractory constipation is a common GI complaint seen by physicians in all practice settings. We have previously shown that p.d. colchicine (0.6 mg t.i.d.) increases the number of spontaneous bowel movements, hastens GI transit, and improves GI symptoms in patients with chronic constipation during an 8-wk, open-label therapeutic trial. The aim of this study was to determine if p.d. colchicine will increase spontaneous bowel movements and accelerate colonic transit in patients with idiopathic chronic constipation in a randomized, placebo-controlled, crossover trial.

METHODS

A total of 16 patients (15 women, one man) with a mean age of 47 yr (age range 25-89) with chronic idiopathic constipation who were refractory to standard medical therapy participated in the study. Patients randomly received either colchicine 0.6 mg p.o. t.i.d. or an identical placebo p.o. t.i.d. for a total of 4 wk in a double-blind, crossover fashion. Patients recorded their daily number of bowel movements and daily symptoms of daily nausea, abdominal pain, and bloating. Mean colonic transit was calculated at baseline, weeks 6 and 12.

RESULTS

Colchicine increased the number of bowel movements and accelerated colonic transit compared with baseline and placebo conditions. There were no significant differences between conditions on ratings of nausea and bloating. During colchicine administration, mean abdominal pain was greater than the baseline or placebo conditions, however, the pain decreased significantly by the last week the patient was on colchicine.

CONCLUSION

Colchicine increases the frequency of bowel movements and hastens colonic transit in patients with chronic constipation. Colchicine may be an effective agent available to practitioners to treat a subset of patients with chronic constipation who are refractory to standard medical therapy.

Treatment Options for Refractory Childhood Constipation

Constipation in children is very common. Childhood constipation responds successfully to medical therapies, behavioral modifications, or a combination of both in approximately 70% of children within 2 years of diagnosis. Persistence of constipation is associated with fecal incontinence, recurrent fecal impactions, and significant emotional problems. Refractory constipation that interferes with both the child's function and the family's life requires extensive evaluations in order to uncover its cause and devise appropriate therapeutic strategies. Children with persistent constipation can be divided into three broad categories: 1) those who have functional constipation, 2) those affected by enteric neuromuscular disorders, and 3) those whose constipation is associated with neurologic handicaps. Treatment options vary widely. The majority of patients require more aggressive medical and more intense behavioral interventions. Others benefit from novel approaches, including surgical intervention.

Long-term response to subtotal colectomy in colonic inertia

The purpose of this study was to determine the long-term outcome of patients who had previously undergone subtotal colectomy for severe idiopathic constipation at the University of Florida between 1983 and 1987. In addition, we aimed to determine whether preoperative motility abnormalities of the upper gastrointestinal tract are more common among those patients who have significant postoperative complications after subtotal colectomy. We evaluated 13 patients who underwent subtotal colectomy for refractory constipation between 1983 and 1987 at the University of Florida. Preoperatively, all patients exhibited a pattern consistent with colonic inertia as demonstrated by means of radiopaque markers. Each patient was asked to quantitate the pain intensity and frequency of their bowel movements before and after surgery. In seven patients an ileosigmoid anastomosis was performed, whereas in six patients an ileorectal anastomosis was used. Abdominal pain decreased after subtotal colectomy. Patients with abnormal upper gastrointestinal motility preoperatively experienced greater postoperative pain than those with normal motility regardless of the type of anastomosis. In addition, the number of postoperative surgeries was similar in those patients with abnormal upper motility compared to those with normal motility. Overall, the total number of bowel movements per week increased from 0.5 +/- 0.03 preoperatively to 15 +/- 4.5 (P < 0.007) postoperatively. The results of our study suggest that patients with isolated colonic inertia have a better long-term outcome from subtotal colectomy than patients with additional upper gastrointestinal motility abnormalities associated with their colonic inertia.

Slow Transit Constipation

The diagnosis of slow transit functional constipation is based upon diagnostic testing of patients with idiopathic constipation who responded poorly to conservative measures such as fiber supplements, fluids, and stimulant laxatives. These tests include barium enema or colonoscopy, colonic transit of radio-opaque markers, anorectal manometry, and expulsion of a water-filled balloon. Plain abdominal films can identify megacolon, which can be further characterized by barium or gastrografin studies. Colonic transit of radio-opaque markers identifies patients with slow transit with stasis of markers in the proximal colon. However, anorectal function should be characterized to exclude outlet dysfunction, which may coexist with colonic inertia. Because slow colonic transit is defined by studies during which patients consume a high-fiber diet, fiber supplements are generally not effective, nor are osmotic laxatives that consist of unabsorbed sugars. Stimulant laxatives are considered first-line therapy, although studies often show a diminished colonic motor response to such agents. There is no evidence to suggest that chronic use of such laxatives is harmful if they are used two to three times per week. Polyethylene glycol with or without electrolytes may be useful in a minority of patients, often combined with misoprostol. I prefer to start with misoprostol 200 mg every other morning and increase to tolerance or efficacy. I see no advantage in prescribing misoprostol on a TID or QID basis or even daily because it increases cramping unnecessarily. This drug is not acceptable in young women who wish to become pregnant. An alternative may be colchicine, which is reported to be effective when given as 0.6 mg TID. Long-term efficacy has not been studied. Finally, biofeedback is a risk-free approach that has been reported as effective in approximately 60% of patients with slow transit constipation in the absence of outlet dysfunction. Although difficult to understand conceptually, it is worth attempting and certainly so in patients with associated pelvic floor dyssynergia. Subtotal colectomy with ileorectal anastomosis is often effective in those patients with colonic inertia, normal anorectal function, and lack of evidence of generalized intestinal dysmotility. However, morbidity is significant both early and late in the disease process and must be balanced against current disability. Ileostomy is preferred in the presence of anorectal dysfunction or with associated impairment of continence mechanisms. Similar considerations apply to the patient with disabling functional megacolon. An alternative approach is ileostomy with disconnection of the colon, which is more acceptable to some patients who may hope for future reconnection if recovery occurs. An additional alternative approach for patients with colonic inertia or megacolon who are not good surgical risks is tube cecostomy (or in children, use of the appendix as a conduit to the cecum). This permits either decompression (in megacolon) or antegrade enemas (in colonic inertia). Our surgeons are not enthusiastic about this approach, and I have little experience with it. In general, the use of partial resections of the colon should be discouraged, because marker studies do not define pathophysiology in patients with slow transit constipation.

Slow-transit Constipation

Idiopathic slow-transit constipation is a clinical syndrome predominantly affecting women, characterized by intractable constipation and delayed colonic transit. This syndrome is attributed to disordered colonic motor function. The disorder spans a spectrum of variable severity, ranging from patients who have relatively mild delays in transit but are otherwise indistinguishable from irritable bowel syndrome to patients with colonic inertia or chronic megacolon. The diagnosis is made after excluding colonic obstruction, metabolic disorders (hypothyroidism, hypercalcemia), drug-induced constipation, and pelvic floor dysfunction (as discussed by Wald ). Most patients are treated with one or more pharmacologic agents, including dietary fiber supplementation, saline laxatives (milk of magnesia), osmotic agents (lactulose, sorbitol, and polyethylene glycol 3350), and stimulant laxatives (bisacodyl and glycerol). A subtotal colectomy is effective and occasionally is indicated for patients with medically refractory, severe slow-transit constipation, provided pelvic floor dysfunction has been excluded or treated.

Review article: the therapy of constipation

Constipation is a common symptom that may be idiopathic or due to various identifiable disease processes. Laxatives are agents that add bulk to intestinal contents, that retain water within the bowel lumen by virtue of osmotic effects, or that stimulate intestinal secretion or motility, thereby increasing the frequency and ease of defecation. Drugs which improve constipation by stimulating gastrointestinal motility by direct actions on the enteric nervous system are under development. Other modalities used to treat constipation include biofeedback and surgery. Laxatives and lavage solutions are also used for colon preparation and evacuation of the bowels after toxic ingestions.

Constipation and fecal incontinence in the elderly

Although constipation and fecal incontinence are common symptoms in the elderly, relatively little research has been done to differentiate physiologic changes in rectoanal function resulting from aging and pathologic changes resulting from diseases occurring as patients age. Certain physiologic changes occur in many older patients and may predispose them to the development of constipation or fecal incontinence. These symptoms need the same thoughtful evaluation and management in the elderly as in younger patients. Results of therapy often can be good, leading to alleviation of suffering and the ability to lead a fuller life.

Slow transit constipation

Slow transit constipation is a clinical syndrome predominantly affecting young women, characterized by constipation and delayed colonic transit, occasionally associated with pelvic floor dysfunction. The disorder spans a spectrum of variable severity, ranging from patients who have relatively mild delays in transit but who are otherwise indistinguishable from irritable bowel syndrome patients at one extreme, to patients with colonic inertia or chronic megacolon at the other extreme. Potential mechanisms for impaired colonic propulsion include fewer colonic HAPCs or a reduced colonic contractile response to a meal. The cause of the syndrome is unclear. The treatment is primarily medical; surgery is reserved for patients with severe disease or colonic inertia. Recognition and treatment of pelvic floor dysfunction is crucial for patients treated medically or surgically. Collaborative studies are necessary to determine the pathophysiology of this disorder and to ascertain the efficacy of novel prokinetic agents.

Misoprostol therapeutics revisited

Misoprostol, a prostaglandin E1 analog, is a racemate of four stereoisomers. On administration it rapidly de-esterifies to its active form, misoprostolic acid. Misoprostolic acid is 85% albumin bound and has a half-life of approximately 30 minutes. It is excreted in urine as inactive metabolites. No significant drug interactions have been reported. Besides its gastrointestinal protective and uterotonic activities, misoprostol regulates various immunologic cascades. It inhibits platelet-activating factor and leukocyte adherence, and modulates adhesion molecule expression. It protects against gut irradiation injury, experimental gastric cancer, enteropathy, and constipation. It improves nutrient absorption in cystic fibrosis. Misoprostol has utility in acetaminophen and ethanol hepatotoxicity, hepatitis, and fibrosis. It is effective in asthmatics and aspirin-sensitive asthmatic and allergic patients. It lowers cholesterol and severity of peripheral vascular diseases, prolongs survival of cardiac and kidney transplantation, synergizes cyclosporine, and protects against cyclosporine-induced renal damage. It works against drug-induced renal damage, interstitial cystitis, lupus nephritis, and hepatorenal syndrome. It is useful in periodontal disease and dental repair. Misoprostol enhances glycosoaminoglycan synthesis in cartilage after injury. It prevents ultraviolet-induced cataracts and reduces intraocular pressure in glaucoma and ocular hypertension. It synergizes antiinflammatory and analgesic effects of diclofenac or colchicine and has been administered to treat trigeminal neuralgic pain. It reduces chemotherapy-induced hair loss and recovery time from burn injury, and is effective in treating sepsis, multiple sclerosis, and pancreatitis.

AGA technical review on constipation. American Gastroenterological Association

This literature review and the recommendations therein were prepared for the American Gastroenterological Association Clinical Practice and Practice Economics Committee. The paper was approved by the Committee on March 4, 2000, and by the AGA Governing Board on May 21, 2000.

Approach to patients with refractory constipation

Constipation is a very frequent problem, particularly in elderly patients. Constipation is a common reason for patients to seek medical advice, and it accounts for a large number of different prescription and over-the-counter medications. In many cases, no definite cause can be found. Most patients respond to conservative therapy with increased fiber and fluid intake alone. Patients with constipation that is more difficult to control or with alarm symptoms (eg, blood in stool, sudden onset, weight loss, or decreasing stool caliber) warrant further investigation. A variety of medical, behavioral, and surgical therapies can be employed to help these more refractory patients.

Vasoactive intestinal polypeptide appears to be one of the mediators in misoprostol-enhanced small intestinal transit in rats

BACKGROUND AND AIMS

Prostaglandin analogs have the pharmacologic effect of speeding up small intestinal transit (SIT). It remains unknown whether some gut peptides also mediate this enhancement. We studied the effect of misoprostol on rat SIT and looked at the role of vasoactive intestinal polypeptide (VIP) release during its action.

METHODS

A group of rats initially received oral misoprostol treatment of 1, 10, 50 and 100 microg/kg, respectively. By using orally fed charcoal as a motility marker, the SIT was assessed at 30 min following oral misoprostol treatment. Another group of rats received misoprostol as an intraperitoneal injection in similar doses to the group above. The small intestinal transit was computed for this group at 30 min following misoprostol injection via an instilled radiochromium motility marker that went through a previously placed intraduodenal catheter. The plasma VIP level was measured by using a radioimmunoassay kit.

RESULTS

Neither charcoal evaluated transit nor the plasma VIP level was influenced by the lower doses of oral misoprostol treatment (1 and 10 microg/kg), whereas other doses enhanced SIT and diminished the plasma VIP level (P< 0.01).The similar effects on radiochromium computed SIT (P< 0.01) and plasma VIP levels were obtained in tubed rats following misoprostol intraperitoneal treatment. The SIT results correlated negatively with plasma VIP levels.

CONCLUSIONS

Enhanced SIT and diminished VIP levels are found in rats following misoprostol treatment. It appears that inhibited VIP release is one of the mechanisms in misoprostol-enhanced SIT.

Challenging problems presenting as constipation

Patients who seek medical care for constipation present challenges which may involve communication problems, difficulties in diagnosis, lack of optimal therapy, uncorrectable underlying disorders, or psychiatric issues which complicated management. This review describes some of these challenges, and presents management approaches that may increase the likelihood of satisfactory treatment outcomes. Situations which are reviewed include the diagnostic evaluation of the new patient with constipation; syndromes of uncertain pathophysiology including irritable bowel syndrome, slow transit constipation, and pelvic floor dysfunction; constipation associated with neurologic disorders including spinal cord injury, Parkinson's disease, and multiple sclerosis; and psychiatric issues which complicate the management of constipation, including recognition of associated psychiatric diseases, unusual attitudes toward bowel function, eating disorders, and referral for psychiatric care.

Functional gut disorders: from motility to sensitivity disorders. A review of current and investigational drugs for their management

Functional gut disorders include several clinical entities defined on the basis of symptom patterns (e.g., functional dyspepsia, irritable bowel syndrome, functional abdominal pain, functional abdominal bloating), for which there is no established pathophysiological mechanism. Because there is no well-defined pathophysiological target, treatment should be aimed at symptom improvement. Prokinetics and antispasmodics have been widely used in the treatment of functional gut disorders on the assumption that disordered motility is the underlying cause of symptoms, and symptom improvement is indeed achievable with these compounds in some, but not all, patients with features of hypo- or hypermotility, respectively. In the first part of this review, we cover the basic pharmacology and discuss the rationale for the clinical use of prokinetics and antispasmodics. On the other hand, in the past few years, the explosive growth in the research focusing on visceral sensitivity and visceral reflexes has suggested that at least some patients with functional gut disorders have altered visceral perception. Thus, the second part of the review covers these developments and focuses on studies addressing the issue of drugs modulating visceral sensitivity.

Management of gastrointestinal motility disorders. A practical guide to drug selection and appropriate ancillary measures

The focus of management of gastrointestinal motility disorders should be to improve survival and quality of life. Some motor disorders are annoying, but are compatible with virtually normal activity and carry no significant life risk. Conversely, other motor disorders are highly incapacitating and may shorten life expectancy because of complications and nutritional impairment. Management is based first on establishing the correct diagnosis and prognosis; secondly, on adjusting therapy to the severity of illness; and thirdly, on preventing significant complications. Simple recommendations on appropriate changes in lifestyle and reassurance may suffice in mild cases. Pharmacological therapy and, exceptionally, surgical or nutritional measures may be required in other patients. Generally, pharmacological agents should be directed towards correcting specific pathophysiological abnormalities, but this is not always possible. Symptomatic relief may be achieved on an empirical basis. Long term treatment may often require the combination of different therapeutic approaches either sequentially or simultaneously.