Possible Causes of Alternating Constipation and Diarrhea

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Dealing with constipation and diarrhea at the same time can be confusing and uncomfortable. 

Usually, constipation means you go to the bathroom less often, and your stool is hard. Diarrhea is the opposite, with stool that is loose and watery. But sometimes, people can have both problems one after the other, or even at the same time.

When constipation and diarrhea happen at the same time, it might be because of a blockage in the digestive system (paradoxical diarrhea). This can cause watery stool to leak out unexpectedly, which looks like diarrhea. In other words, constipation can cause diarrhea. 

Alternating constipation and diarrhea are often a sign of a common gut problem called IBS-M, short for Irritable Bowel Syndrome with Mixed bowel habits. They may also occur due to PMS.

In this article, I review why these bathroom troubles happen. I’ll explain what these conditions feel like, how doctors figure out if you have them, and ways to help you feel better.

Looking for a provider who has experience in gut health who will take the time to learn about your struggles and help you develop a plan to reverse your condition? Colorado residents can schedule a free consultation with PrimeHealth today.

Do You Have IBS-M, Paradoxical Diarrhea, or Period Poops?

This table compares the 3 common causes of constipation alternating with diarrhea to better understand what you may be experiencing:

IBS-MParadoxical DiarrheaPeriod Poops
Alternating or simultaneous constipation and diarrhea?AlternatingSimultaneousAlternating
Abdominal pain relieved by a bowel movement?YesIt depends; pain may not be relieved until the fecal impaction has been removedUsually
Accompanied by bloating and gas?YesNot typicallyYes
Associated with particular days of your menstrual cycleNoNoYes

1. IBS-M

IBS-M is a gastrointestinal disorder that can cause a person to experience both constipation and diarrhea. Unlike IBS-C (where constipation is predominant) or IBS-D (in which diarrhea is predominant), IBS-M is characterized by a generally equal amount of each of these symptoms.

Around 22% of people with irritable bowel syndrome have IBS-M.


The symptoms of IBS-M can vary widely from one individual to another but typically include:

  • Abdominal pain or discomfort that feels relieved after a bowel movement
  • An irregular pattern of constipation and diarrhea
  • Bloating and gas
  • Urgency for bowel movements
  • A feeling of an incomplete evacuation (in other words, you don’t feel like you “got it all out”)


As your provider, I would diagnose IBS-M by first ruling out other digestive tract disorders. This process involves:

  • Discussing your symptoms, dietary habits, and any family history of gastrointestinal disorders (such as inflammatory bowel disease including Crohn’s disease or ulcerative colitis)
  • Conducting a physical exam
  • Using the Rome IV criteria, which require experiencing symptoms at least one day a week in the last 3 months
  • Performing diagnostic tests, such as blood tests or a colonoscopy, especially if you display ‘red flag’ symptoms like weight loss or blood in your stool

If I suspect a serious condition, such as bowel cancer, I will refer you to a gastroenterology specialist for a thorough examination of your small and large intestines.


The treatment for IBS-M is personalized, focusing on relieving symptoms and improving quality of life. Effective treatments often include:

  • Dietary changes, such as adopting a low FODMAP diet, which reduces certain carbohydrates that can trigger symptoms
  • Fiber supplements to help regulate bowel habits
  • Probiotics to support gut health
  • Medications like loperamide (brand name: Imodium) for diarrhea or laxatives for constipation — but always used with care to avoid worsening the other condition (in general, laxatives should be used very infrequently, and I only recommend them on a strictly short-term basis)
  • Mental health care, like cognitive behavioral therapy, to manage the stress that may exacerbate symptoms
  • Regular exercise, which can help reduce the frequency and severity of IBS-M symptoms

Note: Antidepressants are frequently prescribed for IBS relief, but I avoid these medications due to their significant side effects and withdrawal symptoms. In general, my patients have experienced better results with other forms of less invasive treatment.

As your healthcare provider, I’ll work with you to tailor a treatment plan that fits your lifestyle and helps manage your symptoms effectively. My patients are frequently able to reverse IBS completely!

Remember, every person with IBS-M is unique, and what works for one individual may not work for another. It’s important to approach treatment with patience and an open mind towards finding what works best for you.

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2. Paradoxical Diarrhea

Paradoxical diarrhea (sometimes called overflow diarrhea) is a condition where liquid stools leak around a harder stool impaction. It’s like the body’s emergency overflow response when regular pathways are blocked. Unlike IBS-M, paradoxical diarrhea happens simultaneously with constipation.


Paradoxical diarrhea often resembles regular diarrhea, but with some tell-tale differences:

  • Sudden and urgent need to use the restroom
  • Release of watery stools that may be accompanied by harder, impacted stools
  • Possible abdominal cramping, rectal pain, or even bleeding
  • Incontinence of watery stools

If you’re experiencing these symptoms, it could be paradoxical diarrhea, especially if they occur alongside signs of constipation.

Read Next: Can Constipation Cause Nausea? Symptoms, Remedies & 7 Prevention Tips 


Differentiating paradoxical diarrhea from other types of diarrhea involves:

  • A detailed discussion of your bowel habits and symptoms
  • Physical examination, focusing on the abdominal and rectal areas
  • Possibly, imaging tests to identify fecal impaction
  • Monitoring for symptoms that signal more serious health issues, like persistent rectal bleeding, weight loss, or signs of dehydration

Overflow diarrhea in children can occur if your child holds in bowel movements to prevent the pain caused by constipation (which makes the constipation worse).


The treatment strategy for paradoxical diarrhea aims to address the impaction and prevent its recurrence. For the best results, you’ll need to work with a healthcare provider and consider dietary and lifestyle changes to implement on your own.

  • Manual disimpaction conducted by a physician may be necessary in severe cases
  • Enemas or suppositories can help clear the lower digestive tract (always use enemas and suppositories under the guidance of your provider)
  • Short-term use of laxatives may help (do not take laxatives on a long-term basis)
  • Increase water intake to soften stools and aid in regular elimination
  • Introduce a diet rich in whole grains and fiber to promote digestive tract health
  • Increase magnesium intake to promote natural peristalsis and elimination 
  • Engage in regular physical activity to encourage bowel regularity
  • Consider probiotics, herbs, and fiber supplements, but consult with a healthcare provider for personalized advice

3. Period Poops

Many women notice a shift in their bowel habits during menstruation, often referred to colloquially as “period poops.” Gut-related side effects during PMS and your period are part of the body’s complex response to hormonal changes and shouldn’t be a cause for alarm.

While you don’t need a diagnosis to know if your digestive changes are related to your cycle, talk to your provider if you experience severe PMS symptoms or are concerned that you may have another condition (like IBS).

In some cases, IBS and period poops can come together to create a perfect storm. IBS symptoms may present differently in females than males due, in part, to the menstrual cycle.


During menstruation, the body increases its production of prostaglandins, which may lead to:

  • A change in bowel habits, swinging from constipation to diarrhea
  • More frequent bowel movements
  • Bloating or abdominal discomfort
  • Looser stools or even an urgent need for bowel evacuation

Specifically, this prostaglandin increase makes your intestines contract more frequently. In general, it’s slightly more common for women to experience diarrhea during this time rather than constipation, but it’s very possible to have diarrhea and constipation together during PMS.

Note for tampon or menstrual-cup wearers: The orientation of the muscles on your pelvic floor means that straining to go to the bathroom while constipated can cause your tampon or menstrual cup to fall out more easily. Straining, in general, should be limited whenever possible to prevent hard stool from damaging your rectum or causing tears. 

Always use proper soaps/solutions to clean your menstrual cup after contacting toilet water before re-inserting it.

Read Next: A Gut-Friendly Guide to Drinking Coffee With IBS 


Here are some natural and effective remedies to ease digestive discomfort during your period:

  • Maintain a balanced diet with plenty of fiber from sources like fruits, vegetables, and whole grains — this can help manage both constipation and diarrhea.
  • Stay hydrated to support digestive health and reduce bloating.
  • Consider gentle exercise, which can help reduce inflammation and promote regular bowel habits.
  • Over-the-counter remedies like ibuprofen can reduce the production of prostaglandins, easing symptoms.
  • For some, reducing intake of dairy products, caffeine, refined sugar, and high-fat foods might alleviate digestive symptoms during menstruation.

Not sure where to start for a balanced diet? Get PrimeHealth’s Metabolic Clearing Cookbook, designed by our provider team to help you cook delicious, anti-inflammatory meals.

How to Support Better Digestive Health

To support better digestive health, integrating holistic and scientifically backed approaches can be beneficial. 

  • Following a specialized diet that avoids triggers, like foods high in FODMAPs, and includes low-FODMAP foods can significantly improve symptoms​​. If you have celiac disease or a gluten intolerance, cut out gluten. Lactose in milk products is another common trigger for lactose intolerance, which is very common in digestive disorders.
  • Engaging in intermittent fasting might also help, as it has been shown to improve a range of IBS symptoms​. 
  • Regular physical activity, particularly low-intensity exercises like yoga, can alleviate the severity of IBS symptoms​. 
  • Managing stress is crucial, as IBS is a stress-sensitive disorder
  • Mindfulness meditation and stress-reduction techniques have been associated with improvement in gastrointestinal symptoms and overall quality of life​​. 

These practices are all effective natural remedies for IBS and can contribute to maintaining good digestive and bowel health.

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Signs that your digestive health might be suffering include persistent stomach pain, bloating, or changes in bowel habits. If these symptoms persist, talk to your provider about underlying causes, such as leaky gut syndrome.


Are alternating constipation and diarrhea a sign of cancer?

Constipation alternating with diarrhea is not a definitive sign of cancer unless accompanied by other symptoms, such as:

  • Unexplained weight loss
  • Blood in stool (usually, this looks like black, tarry stools)
  • Persistent abdominal pain

Is it possible to have constipation and diarrhea at the same time?

Yes, it is possible to have constipation and diarrhea simultaneously. This is often referred to as paradoxical diarrhea, where liquid stool leaks around a solid fecal impaction.

Can constipation give you diarrhea?

Constipation can lead to a condition known as overflow diarrhea, where liquid stool moves around the impacted fecal matter in the intestines. Again, this is considered paradoxical diarrhea.

What are some foods that cause IBS?

Foods that commonly trigger IBS symptoms include:

  • High-FODMAP foods
  • Dairy products for those who are lactose intolerant or sensitive
  • Gluten for individuals with celiac disease or gluten sensitivity
  • Other known personal triggers like spicy or fatty foods

To learn your own dietary triggers, follow an elimination diet by removing all potentially triggering foods from your diet for 2-4 weeks, then introducing them back in one at a time every 2 weeks.

Are constipation and diarrhea common during pregnancy?

Yes, fluctuations in bowel habits, including constipation and diarrhea, are common during pregnancy due to hormonal changes and the physical pressure of the growing uterus on the intestines. Constipation is most common during pregnancy due to large increases in progesterone hormone production. 

Support for Better Gut Health in Colorado

PrimeHealth’s providers work with patients to develop comprehensive plans for better gut health. If you’ve been struggling with chronic gut issues and are ready to reclaim your health, schedule a consultation today!


  1. Kibune-Nagasako, C., García-Montes, C., Silva-Lorena, S. L., & Aparecida-Mesquita, M. (2016). Irritable bowel syndrome subtypes: Clinical and psychological features, body mass index and comorbidities. Revista Española de Enfermedades Digestivas, 108(2), 59-64.
  2. Schmulson, M. J., & Drossman, D. A. (2017). What is new in Rome IV. Journal of neurogastroenterology and motility, 23(2), 151.
  3. Radziwon, C. D., & Lackner, J. M. (2017). Cognitive behavioral therapy for IBS: how useful, how often, and how does it work?. Current gastroenterology reports, 19, 1-8.
  4. Kułak-Bejda, A., Bejda, G., & Waszkiewicz, N. (2017). Antidepressants for irritable bowel syndrome—A systematic review. Pharmacological Reports, 69(6), 1366-1379.
  5. InformedHealth.org. Signs of colorectal cancer. 2006 Feb 14 [Updated 2017 Jan 26].
  6. Cozma-Petruţ, A., Loghin, F., Miere, D., & Dumitraşcu, D. L. (2017). Diet in irritable bowel syndrome: What to recommend, not what to forbid to patients!. World journal of gastroenterology, 23(21), 3771.
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