Clinical management of constipation

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Reference: May-June 2025 | Issue 3 | Vol 18 | Page 42

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The management of constipation involves a thorough assessment, identification of potential causes, and a multifaceted approach tailored to the individual

Constipation is a common gastrointestinal disorder that impacts individuals across all age groups, affecting both overall health and quality of life. It is characterised by infrequent bowel movements, difficulty passing stool, and the sensation of incomplete bowel evacuation.¹

Prevalence varies widely, with studies estimating that approximately 12-19 per cent of the global population experiences constipation, with a higher incidence among older adults and those in long-term care settings.² It is a common complaint in primary care and hospital settings, accounting for a substantial proportion of healthcare visits. Incidence tends to increase with age and is projected to rise in coming years.³ Functional constipation is common in childhood, with a prevalence of almost 30 per cent worldwide.¹

Pathophysiology

The pathophysiology of constipation is complex and can be categorised into primary (functional) and secondary causes. Primary constipation includes normal transit constipation, slow transit constipation, and defecatory disorders.

Normal transit is the most common form, in which stool moves through the intestines at a typical rate, but individuals experience a sensation of difficulty with defecation. Slow transit constipation results from impaired colonic motility, leading to prolonged stool retention.

Defecatory disorders involve dysfunction of the pelvic floor muscles or rectal abnormalities, impeding stool evacuation.^1,2,4 Unlike functional constipation, where underlying factors may be apparent, chronic idiopathic constipation lacks a clear physiological or anatomical explanation for the persistent discomfort and irregularity in defecation.¹

Secondary constipation arises from various medical conditions such as hypothyroidism, diabetes mellitus, neurological disorders (eg, Parkinson’s disease, multiple sclerosis), medications (eg, opioids, anticholinergics, calcium channel blockers), and structural abnormalities (eg, colorectal cancer, strictures).

The increasing use of opioid medications for pain management has been associated with a rise in opioid-induced constipation, particularly in palliative care and post-surgical patients. Dietary changes, sedentary lifestyles, and increased stress levels contribute to the rising prevalence of constipation in modern society.^1,2,4

Symptoms

Patients with constipation may present with symptoms such as infrequent bowel movements (less than three times per week), hard or lumpy stools, excessive straining, a sensation of incomplete evacuation, and abdominal discomfort or bloating. In some cases, constipation may be associated with nausea, loss of appetite, or psychological distress.^1,2,5

Chronic constipation can lead to complications such as haemorrhoids, anal fissures, rectal prolapse, and faecal impaction. Alarm symptoms such as rectal bleeding, unexplained weight loss, anaemia, or a family history of colorectal cancer warrant further investigation.^1,2,4,5

Diagnosis

A thorough clinical evaluation is important for appropriate management of constipation. A detailed patient history should include bowel movement frequency, stool consistency (using the Bristol Stool Chart), dietary habits, fluid intake, medication history, physical activity, and associated symptoms. A physical examination, including an abdominal assessment and digital rectal examination, can provide valuable diagnostic clues. In certain cases, further diagnostic tests such as blood tests, colonoscopy, anorectal manometry, and colonic transit studies may be required to determine the underlying cause.^1,2

The Rome IV criteria are the internationally recognised standards for diagnosing functional gastrointestinal disorders, including constipation. The criteria help differentiate functional constipation from other conditions – such as irritable bowel syndrome with constipation (IBS-C) – based on specific symptom patterns. These criteria require the presence of at least two of the following symptoms for a duration of at least three months:

• Straining during at least 25 per cent of defecations;
• Lumpy or hard stools in at least 25 per cent of defecations;
• Sensation of incomplete evacuation in at least 25 per cent of defecations;
• Sensation of anorectal obstruction in at least 25 per cent of defecations;
• Manual manoeuvres needed to facilitate defecation in at least 25 per cent of defecations;
• Fewer than three spontaneous bowel movements per week.^1,6

The Paediatric Rome IV criteria for diagnosing functional constipation require the presence of at least two specific symptoms for a defined duration. In infants and children up to four years old, these symptoms must persist for at least one month, while in children older than four, they should be present for a minimum of two months.

Indicators include having fewer than three spontaneous bowel movements per week, experiencing at least one episode of faecal incontinence per week after achieving full bowel control, and displaying a history of faecal retention or withholding behaviours. Passing hard and painful stools, the presence of a large faecal mass on digital rectal examination, or passing stools of such large diameter that they obstruct the rectal outlet or toilet are also considered diagnostic features.¹

Treatment

The cornerstone of constipation management is lifestyle and dietary modification. Increasing dietary fibre intake to 25-30 grams per day from sources such as fruits, vegetables, whole grains, and legumes can improve stool bulk and frequency. Adequate hydration, with a recommended intake of at least 1.5-2 litres of water per day is important to prevent stool hardening. Regular physical activity improves gastrointestinal motility and is beneficial in alleviating constipation. Establishing a consistent bowel routine and responding promptly to the urge to defecate can further improve bowel habits.^1,2,6,7

Pharmacological therapy is considered when lifestyle modifications alone are insufficient. First-line pharmacological treatment includes bulk-forming laxatives such as psyllium, which increase stool volume and facilitate colonic movement. Osmotic laxatives, including polyethylene glycol and lactulose, work by drawing water into the bowel to soften stool and promote peristalsis. Stimulant laxatives such as bisacodyl and senna induce bowel movements by stimulating colonic muscle contractions and are useful for short-term relief. Stool softeners are sometimes used, although their efficacy is limited.^1,3,4,6,7

In cases of refractory constipation, newer agents which enhance intestinal fluid secretion and motility may be considered. Prucalopride, a serotonin 5-HT4 receptor agonist, is another option that accelerates colonic movement and is particularly useful in chronic idiopathic constipation. Studies have demonstrated that these newer agents significantly improve bowel function and quality of life in patients with chronic constipation.^1,2,6

For patients with defecatory disorders, biofeedback therapy is an effective intervention. Biofeedback retraining involves pelvic floor muscle exercises guided by real-time feedback, improving coordination and facilitating normal defecation.³ This therapy is particularly beneficial for patients with dyssynergic defecation. In severe cases unresponsive to conventional treatments, surgical interventions such as colectomy may be considered, although this is reserved for highly selected patients with significant motility disorders.³

Considerations in geriatric patients, hospital settings, and cancer patients

Constipation is particularly prevalent among older adults, affecting up to 40 per cent of individuals over the age of 65. Age-related changes in colonic motility, reduced physical activity, polypharmacy, and dietary modifications contribute to constipation in this population. Management should focus on lifestyle interventions, medication review to identify contributing drugs, and careful use of laxatives to avoid over-reliance on stimulant agents. Older adults are also more prone to complications such as faecal impaction and rectal prolapse, making early intervention important.^2,6,7

It is important to recognise patients who either have or are at risk of developing constipation during their hospital stay. Constipation is frequently overlooked in hospital settings where patients may present with more urgent conditions that require immediate care. Detecting constipation can be difficult in elderly patients, those in residential care, individuals on sedatives, and those who are mechanically ventilated, as these patients may have difficulty communicating or may not be fully aware of their symptoms.

Opioid-induced constipation is a common cause of constipation in hospitalised patients. Managing constipation in hospitalised patients requires a personalised approach, as the effectiveness of certain treatments can vary based on the underlying pathophysiology of the condition.⁸

The management of cancer-related constipation has become a key area for improvement in Ireland, as it is a widespread issue that significantly affects quality of life, but is often under-recognised and inadequately treated. The prevalence of this condition is estimated to range from 32-87 per cent, depending on the study population and methodology, with the highest rates seen in patients receiving opioids. This is notably higher than the general prevalence of constipation in adults.

Constipation can lead to various complications for this already burdened patient group, including pain, loss of appetite, nausea, and vomiting. It may also contribute to the development of haemorrhoids, anal fissures, urinary retention, bowel obstruction, and delirium.⁹

Paediatric constipation

Constipation in children is common and varies by age and developmental stage. Infants may experience constipation when transitioning to solid foods, while toddlers and school-aged children may develop withholding behaviours due to painful defecation, stress, or toilet avoidance. Most cases are functional, but organic causes such as Hirschsprung’s disease, hypothyroidism, or spinal abnormalities should be ruled out, particularly if red flags like poor growth, vomiting, or neurological signs are present.

Key contributing factors include low fibre and fluid intake, stool withholding, and medications like opioids or iron supplements. Management focuses on dietary modifications, toilet training, and laxatives if needed, with specialist referral for persistent or severe cases.^1,10

Constipation in pregnancy

Pregnant women frequently experience constipation due to hormonal changes, reduced intestinal motility, and pressure from the growing uterus on the intestines. Up to 38 per cent of pregnant women report constipation symptoms, which can occur at any stage of pregnancy, but it is most prevalent during the first two months due to the rise in progesterone levels. The condition is more common in multiparous than in primiparous women, likely due to potential damage to the pelvic floor muscles and the pudendal nerve.¹¹

Management should focus on dietary modifications, adequate fluid intake, and safe pharmacologic interventions such as bulk-forming and osmotic laxatives. Stimulant laxatives should be used with caution, and certain medications, such as mineral oil and castor oil, should be avoided due to potential risks to the foetus.

Further research is needed to better understand the causes of constipation and identify effective prevention strategies to reduce its prevalence during pregnancy. Educational programs that emphasise proper nutrition and encourage moderate physical activity throughout pregnancy are important.^11,12

Emerging therapies and future directions

Research into the gut microbiome has shed light on its role in constipation, with studies indicating that alterations in gut bacteria composition may contribute to colonic motility disorders. Probiotic and prebiotic therapies are being explored as potential treatments.¹³

Neuromodulation therapies, including sacral nerve stimulation and transcutaneous electrical nerve stimulation, have shown promise in refractory constipation cases.¹⁴ Several promising new compounds are currently in development, with some already evaluated in human trials. Further clinical trials are needed to establish the long-term efficacy and safety of these novel treatments.¹⁵

Conclusion

Constipation is a common and complex condition that requires a multifaceted, patient-centred approach to management. While dietary and lifestyle modifications form the foundation of treatment, pharmacological therapies, and advanced interventions such as neuromodulation provide valuable options for those with more refractory cases.

As research into the pathophysiology of constipation continues to evolve, particularly with regards to the gut microbiome and novel therapeutic agents, there is potential for more effective and targeted treatments. Integrating these advancements, alongside prioritising patient education and personalised care plans, is important to optimising outcomes and enhancing the quality of life for individuals affected by constipation.

Ongoing research and a continued focus on patient-centred care are essential for refining the management of constipation and ensuring the best possible outcomes for patients.