“If this blog helped you out, don’t keep it to yourself—share the link on your socials!” 👍 “Like what you read? Spread the love and share this blog on your social media.” 👍 “Found this useful? Hit share and let your friends know too!” 👍 “If you enjoyed this post, please share the URL with your friends online.” 👍 “Sharing is caring—drop this link on your social media if it helped you.”

Saturday, August 16, 2025

Constipation


Introduction

Constipation is a common gastrointestinal complaint defined by infrequent, difficult, or incomplete bowel movements. It may present as:

  • Fewer than three bowel movements per week,

  • Passage of hard or lumpy stools,

  • Straining during defecation, or

  • A sensation of incomplete evacuation.

Constipation can be acute (new onset, often secondary to dietary or medication changes) or chronic (lasting >3 months). It can significantly impair quality of life and may reflect functional bowel disorders (like irritable bowel syndrome with constipation – IBS-C) or secondary causes (neurological, metabolic, structural).

Epidemiology

  • Prevalence: 12–19% of the general population; higher in elderly and females.

  • Peaks in:

    • Elderly adults (due to immobility, comorbidities, polypharmacy).

    • Pregnant women (hormonal changes, mechanical factors).

  • One of the leading reasons for laxative use and gastroenterology referrals.

Etiology

1. Primary (Functional) Constipation

  • Normal transit constipation: Stool moves at normal speed but perceived as difficult.

  • Slow transit constipation: Delayed passage through colon.

  • Pelvic floor dysfunction (dyssynergia): Impaired coordination of pelvic floor and anal sphincter during defecation.

2. Secondary Constipation

  • Medications:

    • Opioids (morphine, codeine, oxycodone).

    • Anticholinergics (atropine, tricyclic antidepressants).

    • Calcium channel blockers (verapamil, diltiazem).

    • Iron supplements.

    • Antacids containing aluminum or calcium.

  • Metabolic/Endocrine: Hypothyroidism, hypercalcemia, diabetes mellitus, pregnancy.

  • Neurological: Parkinson’s disease, multiple sclerosis, spinal cord injury.

  • Structural/Mechanical: Colorectal cancer, strictures, rectocele.

Pathophysiology

  • Reduced stool water content from excessive absorption in the colon.

  • Impaired colonic motility (slow transit).

  • Outlet obstruction due to pelvic floor dysfunction or rectal anatomical abnormalities.

  • Altered gut-brain interaction in functional bowel disorders.

Clinical Features

  • Infrequent stools (<3 per week).

  • Hard, dry, pellet-like stools.

  • Straining during defecation.

  • Sensation of incomplete evacuation.

  • Abdominal bloating or discomfort.

  • Rectal pain or bleeding from anal fissures/hemorrhoids.

Alarm features (red flags) requiring urgent evaluation:

  • Onset after age 50.

  • Blood in stool or melena.

  • Unintentional weight loss.

  • Iron-deficiency anemia.

  • Family history of colorectal cancer or IBD.

Complications

  • Hemorrhoids.

  • Anal fissures.

  • Fecal impaction.

  • Rectal prolapse.

  • Urinary retention (in children/elderly).

Diagnosis

1. History and Examination

  • Onset, duration, stool frequency, stool consistency (Bristol Stool Form Scale).

  • Medication history.

  • Lifestyle factors (diet, hydration, activity).

  • Digital rectal exam: assess tone, impaction, masses.

2. Rome IV Criteria for Functional Constipation

At least 2 of the following in ≥25% of defecations:

  • Straining, lumpy/hard stools, sensation of incomplete evacuation, sensation of obstruction, manual maneuvers, <3 bowel movements/week.
    Symptoms present for ≥3 months (with onset ≥6 months prior).

3. Investigations (if indicated)

  • CBC, thyroid function, calcium, glucose (if secondary causes suspected).

  • Colonoscopy (if alarm features present).

  • Colonic transit studies, anorectal manometry (in refractory cases).

Management

1. General Measures

  • Dietary fiber: 20–35 g/day (fruits, vegetables, whole grains).

  • Hydration: 1.5–2 liters/day.

  • Exercise: Regular physical activity improves motility.

  • Toileting habits: Routine time after meals, proper positioning (squat or footstool to elevate legs).

2. Pharmacological Treatment

a) Bulk-Forming Laxatives (first-line in mild cases)

  • Psyllium husk: 3.4 g orally 1–3 times daily with water.

  • Methylcellulose: 2 g orally 1–3 times daily.

  • Safe, but require adequate hydration.

b) Osmotic Laxatives

  • Draw water into bowel, soften stool.

  • Lactulose: 15–45 mL orally daily (may cause bloating, gas).

  • Polyethylene glycol (PEG 3350): 17 g powder in water daily; titrate as needed.

  • Magnesium hydroxide (milk of magnesia): 30–60 mL orally at bedtime.

c) Stimulant Laxatives

  • Increase colonic peristalsis. Useful for short-term or refractory constipation.

  • Senna: 15–30 mg orally at bedtime.

  • Bisacodyl: 5–15 mg orally daily, or 10 mg rectal suppository.

  • Not for long-term use (risk of dependence, electrolyte imbalance).

d) Stool Softeners

  • Docusate sodium: 100–300 mg orally daily.

  • Reduce surface tension → stool softening.

e) Lubricants

  • Mineral oil: 15–45 mL orally daily (not recommended long-term due to aspiration risk).

f) Secretagogues & Prokinetics (for chronic/refractory cases)

  • Lubiprostone: 24 mcg orally twice daily.

  • Linaclotide: 145–290 mcg orally once daily before meals.

  • Prucalopride (5-HT4 agonist): 2 mg orally once daily.

g) Opioid-Induced Constipation

  • Naloxegol: 25 mg orally once daily.

  • Methylnaltrexone: 12 mg SC every other day.

3. Rectal Therapies

  • Glycerin suppositories: For quick relief, especially in children/elderly.

  • Phosphate enemas: For fecal impaction, not for chronic use.

4. Treatment of Secondary Causes

  • Adjust or discontinue causative medications if possible.

  • Manage underlying metabolic, neurological, or structural disorders.

Prognosis

  • Most patients improve with lifestyle measures and appropriate laxative use.

  • Chronic constipation may persist but can be managed effectively.

  • Untreated cases may lead to fecal impaction or complications requiring hospitalization.

Prevention

  • High-fiber diet and adequate hydration.

  • Regular physical activity.

  • Avoid unnecessary constipating medications.

  • Early recognition and treatment of bowel habit changes.

Future Directions

  • Development of novel prokinetic agents with better safety profiles.

  • Use of gut microbiome modulation (probiotics, prebiotics, fecal microbiota transplant) in functional constipation.

  • AI-based personalized treatment algorithms for chronic constipation and IBS-C.




on

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)