Alternating diarrhea and constipation: Can both occur at the same time?

Diarrhea is the passage of watery stool at least three times daily, while constipation is the passage of hard, dry stool, usually less than three times a week. Can both occur simultaneously? Find out in this article.

Key takeaways

  • Diarrhea is a condition that causes one to pass soft, watery stools frequently, while constipation causes hard, dry infrequent bowel movements.
  • While both are contrasted conditions, diarrhea, and constipation can occur at the same time—though rarely.
  • Diarrhea and constipation are common gastrointestinal symptoms that a range of factors, including dietary factors and medical conditions, can cause. A doctor can help diagnose both conditions and recommend treatments.

Diarrhea and constipation are both common gastrointestinal problems that can disrupt a person’s daily life and cause great discomfort.

Diarrhea and constipation often occur independently of each other, but on some occasions, a person might have diarrhea and constipation at the same time.

Understanding both conditions is vital to managing them and improving your digestive health.

In this article, we’ll discuss diarrhea and constipation, their causes, and the impact they can have on your health.

What is diarrhea?

Diarrhea is the passage of liquid stools three or more times daily. An estimated 1.7 billion people worldwide suffer from diarrhea, with a high occurrence rate in countries in sub-Saharan Africa and South Asia.

There are three clinical forms of diarrhea, namely:

  • Acute watery diarrhea, which lasts two weeks or less.
  • Acute bloody diarrhea is defined by the sudden presence of blood in the stool. It can last for several days.
  • Chronic diarrhea which is a term used when diarrhea exceeds 4 weeks. However, if it ranges between 2-4 weeks, it is known as persistent diarrhea.

Some other types of diarrhea include:

  1. Secretory diarrhea is the continuous secretion of important ions into the intestines which causes an influx of fluid into the intestines.
  2. Inflammatory diarrhea which is caused by autoimmune diseases like celiac disease and irritable bowel disease. 
  3. Osmotic diarrhea: When substances like lactose and fructose fail to digest, they increase the water in the intestinal tract. When the excess water cannot be absorbed, the stool becomes watery.

What is constipation?

Constipation is a medical condition where a person passes stools less than three times a week. Because of the lengthy intervals between passing stools, the colon absorbs the moisture in the stool, leaving it hard, dry, and painful to excrete.

Studies have shown that constipation affects at least 14% of people worldwide, with people assigned females at birth and older adults at a higher risk.

Constipation can be classified into two types based on its cause;

  • Primary Constipation: This is caused by problems with the muscles and nerves in the colon which prevents normal bowel movements.
  • Secondary Constipation: This is caused by underlying medical conditions such as diabetes or inflammatory bowel syndrome (IBS) or as a side effect of certain medications such as opioid pain relievers and diuretics.

Can diarrhea and constipation occur together?

Diarrhea and constipation are on opposite ends of the stool spectrum, with one characterized by loose, watery stools and the other by hard, dry stools. Still, constipation and diarrhea occur together in a few cases. One such instance is paradoxical diarrhea.

When stools are not passed out regularly, they accumulate in the rectum, giving rise to a medical condition known as fecal impaction.

Fecal impaction occurs when there’s a large stool mass in the rectum that a person cannot expel because the stool is either too dry or too hard. The rectum enlarges to accommodate the stool, leaving watery excrement around it. And in what seems like an impossible occurrence, waters stool may leak out even with the large stool mass blocking the lower part of the rectum and anal cavity.

This kind of diarrhea is called paradoxical diarrhea or overflow diarrhea. It happens when a soft, watery stool flows over a solid mass of hard stool that is blocking bowel movement. It is usually foul-smelling.

Irritable bowel syndrome is a medical condition that can cause diarrhea and constipation to occur alternatingly—almost simultaneously. A type of IBS called IBS-M can cause episodes of diarrhea and constipation, almost occurring at the same time.

Causes of diarrhea

Diarrhea can be caused by many different factors, some of which are discussed below.

  1. Food Intolerance: Some persons might consume certain foods which could disrupt their digestive system because their body is incapable of digesting such foods properly. For instance, dairy products like milk contain lactose sugar, and recent studies have shown that 65% of the global population does not produce enough lactase enzyme to break down lactose.
  2. Infections: An infection occurs when pathogenic microorganisms gain access into the body. Viral, bacterial, and parasitic infections are some of the primary causes of diarrhea.
  3. Malabsorption: This occurs when a person’s digestive system cannot properly digest nutrients found in food. It could occur due to several medical conditions like Crohn’s disease and cystic fibrosis. Because the body cannot absorb nutrients, growth is stunted, and chronic diarrhea is a notable symptom.
  4. Diabetes: One of the complications of diabetes is enteropathy, a gastrointestinal tract disease. Diabetes is characterized by excess sugar in the blood, which can cause impairment of nerves, including those that control the gastrointestinal tract, thereby causing diarrhea and the reduced ability to control bowel movements. When a person lives with poorly controlled diabetes for a long time, diabetic diarrhea could develop.

Causes of constipation

Constipation does not have one specific cause; the following can increase the chances of developing it:

  • Diabetes: Diabetes can damage the nerves, leading to a condition known as diabetic neuropathy. Damage to nerves in the gastrointestinal tract can make it harder for the bowels to empty properly, and stool could store up, resulting in constipation.
  • Anal fissures: An anal fissure is a tear in the lining of the anal canal, and one major cause of this is persistent diarrhea. The pain experienced by a person with an anal fissure might make them reluctant to empty their bowels, and the feces could build up, resulting in constipation.
  • Eating foods low in fiber: Fiber can’t be digested by the body, but when it is present in the diet, it aids digestion and easy movement of waste products. This means eating foods high in fiber may help prevent or manage constipation.
  • Irritable bowel syndrome: This medical condition comes and goes over a lifetime, and both its cause and cure are unknown. It is characterized by symptoms such as stomach cramps and constipation.
  • Neurological disorders: These are disorders that affect the body’s nervous system, which includes the brain and spinal cord. Damage to nerves that control bowel movement may make it difficult to pass stool, leading to constipation. 
  • Medications: Medications, such as antidepressants, diuretics, and iron supplements used to treat other conditions, could cause constipation as a side effect.

Medical conditions that can cause diarrhea and constipation

Several medical conditions can cause diarrhea and constipation, including:

  • Diabetes: High blood sugar levels can impair nerve function, including the function of nerves in the gastrointestinal tract that controls bowel movement, affecting bowel movement.  
  • Celiac disease: This medical condition is an autoimmune disease where the body’s immune system fights its own cells. The condition causes the body to react to gluten, a natural protein found in rice, wheat, and other cereals. Constipation and diarrhea are some of the symptoms of celiac disease.
  • Irritable bowel syndrome is a lifelong condition affecting the gastrointestinal tract, and it could lead to either stronger or weaker muscle contractions, leading to diarrhea or constipation.
  • Inflammatory bowel disease: This refers to two gastrointestinal conditions, namely Crohn’s disease and ulcerative colitis, which can lead to both diarrhea and constipation.

How to prevent diarrhea and constipation

Preventing diarrhea and constipation depends majorly on making necessary lifestyle changes; some of the changes you can make are itemized below.

Things you can do to prevent constipation include:

  • Drink plenty of water.
  • Eat foods rich in fiber, like fruits and vegetables.
  • Use laxatives as prescribed by your doctor.
  • Once you need to go to the toilet, don’t hesitate.
  • Consume more probiotics, such as yogurt, or use a probiotic supplement.

You can prevent diarrhea by:

  • Washing your hands thoroughly with soap and water
  • Practicing good sanitary measures
  • Cooking your food thoroughly before consumption
  • Getting proper vaccination against pathogenic organisms like rotavirus
  • Consuming probiotics to build up your gastrointestinal tract

How to treat diarrhea and constipation

If you have diarrhea and constipation, especially if they last for a long time, you should talk to your doctor to find out how to treat them.

Your doctor could prescribe medications such as antibiotics while recommending useful probiotics that would nurse you back to health.

There are several self-treatment options that you can follow, and they include:

  • Stay hydrated: Drinking more water helps to replace the lost electrolytes and to encourage regular bowel movements.
  • Exercise and rest: If you have constipation, regular physical movement can stimulate bowel movement as well, while rest is needed for those suffering from diarrhea to gain strength.
  • Eat a balanced diet: Your diet plays an important role in your digestive health, and ensuring you get all important nutrients is a way to stay healthy.

Wrap up

Diarrhea and constipation are common and can affect anyone. They often occur independently but can also occur together.

They can be managed effectively with the right treatment and self-care to prevent them from disrupting your daily activities.

This article has shed more light on their possible causes and several medical conditions which could lead to diarrhea and constipation. By understanding this, you can maintain and improve your digestive health.


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