Constipation

What is constipation?

Constipation can be an uncomfortable condition. However, because it affects millions of people each year, it’s a topic that shouldn’t be ignored. Constipation is defined as^[1] having fewer than three bowel movements in a week. In reality, however, everyone’s bowel habits are different. Some people have multiple bowel movements per day. For them, constipation could mean having a bowel movement only once a day. Others may expect to have just one or two bowel movements a week.In other words, while what’s considered to be constipation is determined on a case-by-case basis, having fewer bowel movements than you normally do may indicate that you are constipated. Constipation most commonly occurs when stool (waste) moves too slowly through the digestive tract, preventing it from being eliminated effectively. Because of this, constipation involves more than just the frequency of bowel movements: it also often causes^[2] dry, hard stools and painful bowel movements. It may also cause you to feel that you haven’t completely emptied your bowels or that you are “backed up.” Constipation can be classified in two ways: sporadic and chronic^[3]. Sporadic constipation is short-lived and has a direct cause (such as diet changes, sickness, or air travel). Chronic constipation, on the other hand, is much longer-lasting. The good news for both those with sporadic and chronic constipation is that there are multiple treatments available, ranging from lifestyle changes to prescription and over-the-counter medications. It’s important to seek prompt treatment for constipation. The longer it takes you to have a bowel movement, the harder it becomes to do so. Additionally, constipation (especially chronic constipation) can be a sign of a more serious underlying health condition.

Chronic constipation

While having occasional bouts of constipation is normal, some people experience constipation that occurs for such a long time that it interferes with daily life. This is known as chronic constipation. Chronic constipation is defined as^[4] infrequent bowel movements or difficulty passing stool that persists for several weeks or longer. People with chronic constipation have ongoing symptoms of infrequent bowel movements, including hard or lumpy stools, straining to have bowel movements, or feeling intestinal blockages. In order to be diagnosed with chronic constipation⁴, a patient must experience at least two of the symptoms of the condition for the last three months.

How common is constipation?

Constipation is very common. In fact, it is one of the most frequent gastrointestinal (GI) complaints among patients in the United States^[5]. At least 2.5 million people seek medical treatment for constipation each year. While constipation is more common in some people than others, anyone can experience constipation from time to time. However, the definition of constipation leaves room for interpretation. Additionally, because bowel habits can vary so much from person to person, what may be considered constipation in one person may not cause any distress or uncomfortable symptoms in another. As a result, the prevalence^[6] of people suffering from chronic constipation in particular may be anywhere from 2–28%.

What causes constipation?

Generally speaking, constipation occurs^[7] when one of two things happens: either stool isn’t passing through the digestive tract quickly enough, or stool can’t be passed through the rectum effectively (or both). Normally, nutrients are absorbed from the food you eat as it passes through your digestive tract. Partially digested food that’s left behind (waste) passes through the small intestine to the large intestine (colon). In the colon, water is absorbed from this waste, producing the solid matter referred to as stool. When you’re constipated, the food you eat may move too slowly through your digestive tract. As a result, the colon has too much time to absorb water from your waste. This causes^[8] the stool to dry out and become hard in consistency, making it harder to pass out of the body. While these symptoms are the result of constipation, the underlying causes of constipation itself can vary widely, from physical blockages or problems to lifestyle choices. Common causes of constipation include⁸:

• Lifestyle causes, including dehydration, physical inactivity, changes in your daily routine, not getting enough fiber, consuming too much dairy, and stress.
• Age and biological sex: Older adults are at a higher risk of experiencing constipation, likely due to having slower metabolisms and more sedentary lifestyles.

Women are also at a higher risk of constipation than men. During pregnancy, the baby can exert pressure on the intestines, causing issues and difficulty when passing stool. Hormonal changes can also cause constipation, leading women who have recently given birth to be more prone to constipation.

• Blockages in the colon or rectum: Blockages or other physical problems that affect the colon (large intestine) or rectum (the endpoint of the colon that terminates at the anus) may slow or prevent stool from moving through the digestive tract.

Examples of these problems include intestinal blockages (bowel obstruction), tiny tears in the skin around the anus (anal fissures), narrowing of the colon (bowel stricture), colon cancer (or other forms of abdominal cancer that press on the colon), rectal cancer, and a herniation (bulge) of the front wall of the rectum through the back wall of the vagina (called a rectocele).

• Problems with the muscles involved in elimination (bowel movement): Problems with the pelvic muscles involved in having bowel movements may result in chronic constipation.

These problems may include having weakened pelvic muscles, having pelvic muscles that don’t correctly coordinate relaxation and contraction (called dyssynergia), and being unable to relax the pelvic muscles to allow for bowel movements (called anismus).

• Certain medications: Strong pain medications, such as opioid narcotics, have all been shown to cause constipation. Examples of opioid narcotics include morphine, oxycodone, methadone, and hydromorphone.

Other drugs that may cause constipation include nonsteroidal anti-inflammatory drugs (NSAIDs, such as naproxen), tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs), antacids containing calcium or aluminum, iron pills, and antihistamine allergy medications, as well as certain blood pressure medications, anticonvulsant/anti-seizure medications, and anti-nausea medications.

• Underlying health conditions: Hormones help to balance the fluids in the body. Health conditions that cause the body’s hormones to become imbalanced (such as diabetes, an underactive thyroid gland [hypothyroidism], an overactive parathyroid gland [hyperparathyroidism], and pregnancy) may all cause constipation.

Many other health conditions may contribute to constipation, including colorectal cancer, irritable bowel syndrome (IBS), diverticulosis, and lazy bowel syndrome (a condition in which the colon retains stool and contracts poorly).

• Problems with the nerves around the colon and rectum: Neurological problems (those that affect the brain and spinal cord) can impact the ability of the muscles in the colon and rectum to contract and move waste through the intestines.

These problems include stroke, multiple sclerosis (MS), Parkinson’s disease, injury to the spinal cord, damage to the nerves that control bodily functions (called autonomic neuropathy).

Risk factors for constipation

Certain factors may increase your risk of developing chronic (frequent or long-term) constipation. These factors, which often overlap with the causes listed above, include^[9]:

• Older age: Older adults tend to get less physical activity, have slower metabolisms, and have less muscle contraction strength along their digestive tracts, all of which can contribute to constipation.
• Biological sex: Women (especially those who are pregnant and have recently given birth) are more prone to constipation, often as a result of hormonal changes.
• Dehydration: This is one of the most common causes of chronic constipation.
• Low fiber intake: Foods that are high in fiber help keep food moving smoothly through the digestive system. Not eating enough fiber can result in constipation.
• Taking certain medications: Some medications (including those listed above) can cause chronic constipation.
• Certain health disorders: As mentioned above, both neurological and digestive disorders can contribute to constipation.
• Physical inactivity: Inactivity is another leading cause of constipation.
• Mental health disorders: Having a mental health condition, such as depression or an eating disorder, may increase your risk of chronic constipation.

Constipation symptoms

The most common symptom^[10] of constipation is having bowel movements less frequently than usual (by definition, fewer than three a week). However, people with constipation often experience a number of additional symptoms, including^[11]:

• Dry, hard, lumpy, or small stools
• Difficulty passing stool
• Abdominal pain (stomach aches or cramping)
• Feeling that you haven’t fully emptied your bowels or that you’re “backed up”
• Frequently relying on Laxatives, enemas, or suppositories in order to have bowel movements
• Bloating, nausea, and fatigue

Depending on the source of your constipation and which treatments you explore, these signs and symptoms could last from a few days to several weeks. In some cases, symptoms can be consistent and ongoing (as with chronic constipation). If your bowel movements stop altogether or if you begin suffering from severe abdominal pain, internal swelling (distention), or rectal bleeding, it’s important that you see your healthcare provider immediately. These may be signs of much more serious health conditions.

Constipation in pregnancy

Unfortunately, constipation and pregnancy^[12] often go hand-in-hand. About half of all women experience constipation at some point during their pregnancy. There are a few reasons for this. On the one hand, pregnancy brings on or exacerbates some of the most common causes of constipation. Limited physical activity, hormonal changes, and high levels of stress and anxiety are all common in pregnant women and likely culprits of constipation. Additionally, the baby’s position in a pregnant woman’s body can put pressure on the intestines, which can prevent stool from moving through the digestive tract. A woman’s diet may also change during pregnancy. Pregnant women who aren’t eating enough fiber drinking enough water may develop constipation. In some cases, a healthcare provider may prescribe iron tablets during pregnancy. These may also be linked to constipation. It’s important to note that pregnant women should not use laxatives because they can cause dehydration (or, in some cases, uterine contractions). It’s also important to avoid taking mineral oils for constipation during pregnancy, as they can impede the body’s ability to absorb nutrients.

Complications from constipation

While constipation is a common condition, problems can develop if you don’t return to your regular bowel movement routine^[13]. Some possible complications of prolonged or severe constipation include^[14]:

• Hemorrhoids: Hemorrhoids occur when the veins around the anus swell, often as a result of straining to have bowel movements. Hemorrhoids can cause pain and itchiness.
• Anal fissures: Hard stool passing through the anus can lead to tiny tears in the anus’ skin called anal fissures.
• Diverticulitis: Constipation can cause stool to become trapped in the rectum. This trapped stool may cause infected pouches to form off the colon wall (called diverticulitis).
• Fecal impaction: Chronic constipation can cause fecal impaction—a buildup of hardened stool that has become stuck in the intestines.
• Stress urinary incontinence: Prolonged, excessive straining while attempting to have bowel movements may damage the muscles of the pelvic floor that help control the bladder. This can cause urine to leak from the bladder (called stress urinary incontinence).
• Rectal prolapse: Also caused by straining, rectal prolapse occurs when a portion of the rectum has been overly stretched and begins to protrude out of the body from the anus.