Chronic Constipation

What counts as chronic constipation

Doctors use the Rome IV criteria. For at least 3 months, with symptoms starting at least 6 months earlier, you have two or more of the following in more than 1 in 4 bowel movements:

• straining
• lumpy or hard stools (types 1 to 2 on the Bristol Stool Form Scale)
• a feeling of incomplete emptying
• a feeling of blockage at the anus
• needing to use fingers or press to help pass stool
• fewer than 3 bowel movements a week

When abdominal pain is the main feature and improves with bowel movements, the diagnosis is usually irritable bowel syndrome with constipation.

Types of chronic constipation

Causes and risk factors

Lifestyle

• low fiber intake (most adults eat well under the recommended 25 to 35 grams)
• not drinking enough fluid
• physical inactivity and immobility
• ignoring the urge to go, irregular routines, travel

Medicines

Opioids, iron and calcium supplements, aluminum antacids, anticholinergics, tricyclic antidepressants, calcium channel blockers (especially verapamil), antipsychotics and some anti-nausea medicines (ondansetron).

Medical conditions

• hypothyroidism, diabetes, high calcium, low potassium
• Parkinson's disease, multiple sclerosis, spinal cord injury
• pregnancy
• depression and eating disorders
• structural problems: rectocele, rectal prolapse, anal fissure, strictures
• colorectal cancer, which can narrow the bowel

Diagnosis

1. History: stool frequency and form, straining, emptying, diet, fluids, medicines, mood and red flags.
2. Examination: abdomen and rectal examination to assess the anal tone, pelvic floor movement, fissures and impacted stool.
3. Blood tests: blood count, thyroid function, calcium and blood sugar if indicated.
4. Colonoscopy: for red-flag features or if due for routine colorectal cancer screening from 45.
5. Specialist tests for difficult cases: anorectal manometry and balloon expulsion test (pelvic floor function), defecography, and colon transit studies.

Treatment

Lifestyle measures

• Fiber: increase gradually to 25 to 35 grams a day from fruit (especially prunes and kiwifruit), vegetables, whole grains and legumes, or use psyllium supplements. Increase slowly to limit bloating.
• Fluids: enough to keep urine pale.
• Exercise: regular physical activity.
• Toilet routine: try after breakfast, when the bowel is most active, and do not ignore the urge.
• Posture: raise your feet on a small stool so your knees are above your hips, lean forward and relax.

Laxatives

Follow label doses and use as advised:

• Bulk-forming: psyllium. Take with plenty of water.
• Osmotic: polyethylene glycol (PEG) is first-line for chronic constipation and safe for long-term use. Magnesium salts and lactulose are alternatives. Avoid magnesium products in kidney disease.
• Stimulant: senna and bisacodyl, effective as needed or regularly.
• Stool softeners: docusate, with limited benefit alone.
• Suppositories and enemas: glycerin or bisacodyl suppositories for outlet problems.

Prescription medicines

When over-the-counter options fail: linaclotide, plecanatide, lubiprostone and prucalopride. Opioid-induced constipation can be treated with peripherally acting opioid antagonists such as methylnaltrexone or naloxegol.

Biofeedback

For pelvic floor dysfunction, biofeedback therapy with a specialist physical therapist teaches you to relax and coordinate the pelvic floor muscles. It helps most people with this type and is more effective than laxatives for it.

Surgery

Rarely needed: for severe slow-transit constipation unresponsive to all treatment, or for structural problems such as large rectoceles or prolapse.

Complications

• hemorrhoids and anal fissures from straining
• fecal impaction, especially in older or immobile people
• rectal prolapse
• urinary retention and bladder symptoms
• reduced quality of life

Frequently asked questions

What causes chronic constipation?

Common causes include low fiber, not drinking enough, inactivity, medicines such as opioids and iron, pelvic floor dysfunction, slow movement of the colon, and conditions like hypothyroidism, diabetes and Parkinson's disease. Often no single cause is found.

What is the best treatment for chronic constipation?

Most people start with more fiber, fluids and exercise, then add an osmotic laxative such as polyethylene glycol. Stimulant laxatives and prescription medicines are options if needed. Pelvic floor problems respond best to biofeedback therapy.

Is it safe to take laxatives every day?

Polyethylene glycol and fiber supplements are considered safe for long-term daily use. Stimulant laxatives are also generally safe when used as directed, despite older concerns. Talk to your doctor if you need laxatives regularly.

When should I worry about constipation?

See a doctor if constipation is new after 45, lasts more than a few weeks despite treatment, or comes with blood in the stool, weight loss, anemia, severe pain or a family history of bowel cancer. Seek emergency care for vomiting with a swollen belly and no gas passed.