Overview

Constipation is a problem with passing stool. Constipation generally means passing fewer than three stools a week or having a difficult time passing stool.

Constipation is fairly common. A lack of dietary fiber, fluids and exercise can cause constipation. But other medical conditions or certain medicines may be the cause.

Constipation is usually treated with changes in diet and exercise or with nonprescription medicines. Constipation may require medicines, changes in medicines or other treatments prescribed by a health care professional.

Long-term constipation, also called chronic constipation, may require treating another disease or condition that can cause or worsen constipation.

Symptoms

Symptoms of constipation include:

  • Fewer than three stools a week.
  • Hard, dry or lumpy stools.
  • Straining or pain when passing stools.
  • A feeling that not all stool has passed.
  • A feeling that the rectum is blocked.
  • The need to use a finger to pass stool.

Chronic constipation is having two or more of these symptoms for three months or longer.

When to see a doctor

Make an appointment with your health care professional if you have constipation with any of the following conditions:

  • Symptoms that last longer than three weeks.
  • Symptoms that make it difficult to do everyday activities.
  • Bleeding from your rectum or blood on toilet tissue.
  • Blood in your stools or black stools.
  • Other unusual changes in the shape or color of stools.
  • Stomach pain that doesn't stop.
  • Weight loss without trying.

Causes

Patterns of bowel movements vary from one person to another. The typical range is three times a day to three times a week. So it's important to know what is typical for you.

In general, constipation occurs when stool moves too slowly through the large intestine, also called the colon. If the stool moves slowly, the body absorbs too much water from the stool. The stool can become hard, dry and difficult to pass.

Lifestyle causes

Slow stool movement may happen when a person does not:

  • Drink enough fluids.
  • Eat enough dietary fiber.
  • Exercise regularly.
  • Use the toilet when there's an urge to pass stool.

Medicines

Constipation may be a side effect of some medicines, particularly opioid pain relievers. Other medicines that may cause constipation include some that treat the following conditions:

  • Pain.
  • High blood pressure.
  • Seizures.
  • Depression.
  • Disorders of the nervous system.
  • Allergies.

Problems with pelvic floor muscles

The muscles that hold up organs at the bottom of the torso are called the pelvic floor muscles. The ability both to relax these muscles and to bear down are necessary to pass stool from the rectum. Problems with weakness or coordination of these muscles can cause chronic constipation.

Blockages in the colon or rectum

Damage or changes to tissues in the colon or rectum can block the passage of stool. Also, tumors in the colon, rectum or nearby tissues can cause a blockage.

Other factors

A number of conditions can affect the work of muscles, nerves or hormones involved in passing stool. Chronic constipation may be linked to any number of things, including:

  • Irritable bowel syndrome.
  • Diabetes.
  • Multiple sclerosis.
  • Nerve dysfunction or damage.
  • Overactive thyroid, also called hyperthyroidism.
  • Parkinson's disease.
  • Pregnancy.

Sometimes, the cause of chronic constipation can't be found.

Risk factors

Factors that may increase your risk of chronic constipation include:

  • Being an older adult
  • Being a woman
  • Getting little or no physical activity
  • Having a mental health condition such as depression or an eating disorder

Complications

Complications of chronic constipation include:

  • Swollen tissues around the anus, also called hemorrhoids.
  • Torn tissues of the anus, also called anal fissures.
  • Hard stools backed up into the colon, also called fecal impaction.
  • Exposed tissues of the rectum that have slipped out of the anal opening, also called rectal prolapse.

Prevention

The following tips can help you avoid developing constipation.

  • Eat lots of high-fiber foods, including vegetables, fruits, beans and whole-grain foods.
  • Eat fewer foods with low amounts of fiber such as processed foods, dairy and meats.
  • Drink plenty of fluids.
  • Stay active and exercise regularly.
  • Don't ignore the urge to pass stool.
  • Create a regular schedule for passing stool, especially after a meal.
By Mayo Clinic Staff