Constipation and Defecation Problems Overview
- How is constipation defined?
Constipation is one of the most frequent gastrointestinal complaints in the United States and Western countries. There are at least 2.5 million doctor visits for constipation in the USA each year, and hundreds of millions of dollars are spent on laxatives yearly.
Many people think constipation means not having a bowel movement every day, but this is not necessarily true. Normal bowel habits vary from person to person. Some people have several bowel movements a day, while others may have as few as three bowel movements per week and still be healthy.
Constipation is generally defined as having bowel movements that are less frequent than your usual pattern and/or having difficulty passing stool. Symptoms of constipation may include:
- Having fewer bowel movements than is normal for you.
- Straining or excessive effort during bowel movements.
- Passing hard, dry, or lumpy stools that are difficult to pass.
- A sensation of incomplete emptying after a bowel movement.
- A feeling of blockage or difficulty passing stool.
The American College of Gastroenterology (ACG) defines constipation based upon symptoms including unsatisfactory defecation with either infrequent stools, difficulty in passing stool or both.
If you notice a new or persistent change in your bowel habits, it is important to discuss it with your healthcare provider. Early evaluation can help identify the cause and guide appropriate treatment.
Causes
- What causes constipation?
Constipation can have many different causes, and in some people, more than one factor may contribute to their symptoms. Constipation most commonly occurs when the stool (waste formed after eating and digestion) moves slowly through the digestive tract. When this happens, too much water is absorbed from the stool, making it hard, dry, and more difficult to pass.
Common causes of constipation include:
- Not drinking enough fluids, which can lead to dehydration and harder stools.
- Dietary changes, especially a diet low in fiber. Fiber helps moving water into the stools to make them softer.
- Decreased physical activity or prolonged inactivity.
Certain medical conditions can also affect the nerves and muscles that help move stool through the intestines, increasing the risk of constipation. These include:
- Diabetes
- Thyroid disorders (especially hypothyroidism)
- Parkinson’s disease
- Multiple sclerosis
- Spinal cord injuries
- Other neurologic disorders
Many medications can slow intestinal movement and contribute to constipation. Common examples include:
- Opioids
- Iron supplements
- Calcium supplements
- Certain blood pressure medications
- Some antidepressants and other prescription medications
Problems with the muscles and nerves of the pelvic floor, which help coordinate the passage of stool from the rectum, can also cause constipation. These conditions may make it difficult to relax or coordinate the muscles needed for a bowel movement.
Less commonly, constipation may be caused by a bowel obstruction (blockage). This can occur due to tumors inside the colon or from conditions affecting nearby organs in the abdomen or pelvis. Although uncommon, bowel obstruction can be a serious medical condition and may require urgent evaluation and treatment.
Diagnosis
- What kind of evaluation should constipated patients undergo?
Medical history and physical examination: A careful medical history and physical examination are usually the most important steps in evaluating constipation. Your healthcare provider will ask about your symptoms, bowel habits, diet, medications, medical conditions, and any recent changes in your health.
The doctor may also examine the rectum with a gloved finger. This exam can help assess:
- The presence and consistency of stool in the rectum
- Whether there is blood in the stool
- The strength and function of the muscles involved in bowel movements
- The presence of a tumor or prolapse
In the majority of the cases a thorough history and physical examination is all that is needed to confirm a diagnosis of constipation and to determine the likely cause.
Your doctor may order an abdominal x-ray to look for excessive build-up of stool which can prompt your doctor to advise a ‘bowel cleanse’. Additional testing may be recommended when the cause of constipation is unclear or if there are concerning symptoms.
Colonoscopy is a procedure that allows your doctor to examine the entire colon using a flexible tube with a camera. Colonoscopy may be recommended if:
- Constipation develops suddenly or represents a significant change from your usual bowel habits
- There is blood in the stool
- You have unexplained weight loss, anemia, or other concerning symptoms
- You are due for colorectal cancer screening
In some cases, a sigmoidoscopy, which examines only the lower part of the colon, may be performed.
Specialized Testing
If constipation persists despite treatment or if a disorder affecting the muscles and nerves of the colon or rectum is suspected, specialized tests may be recommended:
- Colonic transit studies: These tests evaluate how quickly stool moves through the colon. This may involve swallowing capsules containing tiny markers that can be seen on X-rays or a wireless telemetry capsule that tracks movement through the digestive tract.
- Anorectal manometry: A small, flexible tube is placed into the rectum to measure rectal sensation, muscle strength, and coordination during bowel movements.
- Defecography: This imaging test evaluates how the rectum and pelvic floor muscles function during defecation. It may be performed using specialized X-rays or magnetic resonance imaging (MRI).
Treatment
- What are the treatments for constipation?
There are several ways to treat constipation. Increasing water intake and dietary fiber is often the first step. Vegetables, fruit (especially kiwis and prunes), whole-grain breads, and high-fiber cereals are excellent sources of fiber. Bran is an alternative source, although it may cause excessive gas and bloating. To help prevent gas, fiber should be eaten with plenty of fluids.
Laxatives and stool softeners are sometimes needed if if dietary changes are not enough. Most laxatives are safe for long-term uses, if used appropriately.
- Bulking agents, such as psyllium and methylcellulose, are laxatives that help hold water in the stool and add bulk to it. The increased bulk causes movements of the large intestines, making the stool easy to pass. Bulkier stools are softer and easier to pass. Bulking agents act slowly and gently. These agents generally are taken in small amounts at first. The dose is increased gradually until the patient’s bowel movements become regular.
- Osmotic agents are laxatives that draw and retain water in the large intestine, making the stool soft and loose. These laxatives consist of salts or sugars that are poorly absorbed. Some contain magnesium and phosphate, which can be partially absorbed resulting in harm to people with kidney disease.
- Stimulant laxatives contain substances that directly stimulate the walls of the large intestine (such as senna and bisacodyl), causing them to contract. When taken by mouth, they usually produce a bowel movement within 6 to 8 hours. Some are available as suppositories. When taken as suppositories, these laxatives often work in 15 to 60 minutes. Stimulant laxatives are best used for brief periods. If longer use is needed, they may be used daily or every other day, and optimally under a doctor's supervision.
- Enemas: If stool is too hard, tap water enemas may be needed. The patient is asked to lay on their left side, with knees flexed. About 5 to 10 ounces of water, at body temperature, is gently introduced into the rectum and sigmoid colon. The hard stool gets softened and comes out with the water. Prepackaged over-the-counter enemas can be used instead of tap water. In rare cases, if enemas fail to work, a health care worker may need to remove the stool manually using a gloved finger. The patient may then be given a solution containing dissolved salts and polyethylene glycol to help cleanse the bowel. After disimpaction, fiber intake and/or laxatives are usually recommended to help prevent recurrence.
- Prescription medications may work by increasing fluid secretion in the intestine or improving intestinal movement. These are considered when constipation does not respond to over-the-counter treatments. When constipation is caused by opioid medications used for pain control, specific agents that block the effects of opioids on the gut may be helpful.
- Pelvic floor physical therapy and biofeedback: In some cases, constipation is caused by difficulty coordinating the pelvic floor and anorectal muscles. This can be treated with biofeedback therapy or muscle retraining exercises, usually performed under the guidance of trained pelvic floor therapists.
Prevention
- Can constipation be prevented?
A combination of an adequate intake of fluids, adequate exercise, and a high-fiber diet may prevent constipation. Laxatives are sometimes a helpful addition to these measures. For example, when a person needs to take a potentially constipating drug, a stimulant laxative along with increased intake of dietary fiber and fluids helps prevent constipation.
Author(s) and Publication Date(s)
Arnold Wald, MD, MACG, University of Wisconsin School of Medicine and Public Health, Madison, WI – Published June 2004, Updated January 2010, Updated March 2016.
Cuckoo Choudhary, Thomas Jefferson University, Philadelphia, PA – Updated August 2022.
Saad Javed, MD, AHN Medicine Institute, Pittsburg, PA and Jellyana Peraza, MD, Yale New Haven Hospital, New Haven, CT – Updated June 2026.
Constipation 101 Instagram TV Podcast
Patient Links
- International Foundation for Functional Gastrointestinal Disorders
- National Digestive Diseases Information Clearinghouse
- National Institute of Diabetes, Digestive and Kidney Diseases
