Different Types of Constipation: The Importance of Knowing Your Subtype

Constipation is a common yet complex issue that can affect your comfort, quality of life, and overall well-being. As a digestive health dietitian (who also struggles with constipation personally), I’ve become a bit of a constipation connoisseur. And trust me, it’s not as simple as just skipping a few days of bowel movements.

While many people think of constipation as a single condition, it actually has distinct subtypes, each with its own causes and treatment strategies. Whether it’s related to slow gut motility, pelvic floor dysfunction, or a combination of factors, identifying your subtype is key to finding the most effective solutions. If you’re prone to constipation and want to understand how to fix it, this is truly where it all starts.

Understanding what’s driving your symptoms not only helps target the root cause but also prevents trial-and-error approaches that can be frustrating and ineffective. If you’re ready to take control of your symptoms, read my constipation ebook for more info—it’s packed with tips and insights to help you better understand your subtype and find relief. Let’s explore why knowing your constipation subtype can make all the difference in managing this complex condition.

Table of Contents

• Functional Constipation
• IBS-Constipation (IBS-C)
• Slow Transit Constipation
• Pelvic Floor Dysfunction
• Medication-Induced Constipation
• Constipation from Inadequate Energy Intake

Functional Constipation

Functional constipation is what often comes to mind when people think of being constipated. It is characterized by infrequent bowel movements (fewer than three per week), straining, and difficulty passing stool, without an identifiable underlying cause. Although functional constipation is the most common subtype, we often see that many people get lumped into this group or IBS-C (more on this soon). Unfortunately, being put in this category often means people don’t get much further investigation for other potential root causes. It can feel incredibly frustrating – like you’re just left to your own devices to “figure it out”. 

If you experience the following symptoms, you are most likely to have functional constipation:

• Fewer than three bowel movements per week
• Hard, lumpy stools that are difficult to pass
• A sensation of incomplete evacuation after passing stool
• Straining during bowel movements

Irritable Bowel Syndrome with Constipation (IBS-C)

There are a lot of similarities between functional constipation and IBS-C. However, there is one notable difference. IBS (of any type) predominantly involves pain. Although being constipated in general can be uncomfortable and sometimes painful, IBS-C distinctly involves an element of pain. 

If you experience the following symptoms, you are more likely to have IBS-C: 

• Fewer than three bowel movements per week
• Hard, lumpy stools that are difficult to pass
• A sensation of incomplete evacuation after passing stool
• Straining during bowel movements

PLUS

• Pain & discomfort as a predominant feature of your symptoms

I tend to see that the line between these two subtypes is blurry. One helpful visual is to think of constipation as a spectrum – with functional constipation at one end and IBS-C at the other. If more abdominal pain is consistently involved in your symptoms, you are more likely to fall into the IBS-C category. 

In my experience, most cases of severe constipation can cause pain, and addressing the constipation or ‘clearing out’ the bowel often alleviates that pain for many individuals. However, if symptoms like bloating, discomfort, and pain persist even after the bowels are cleared, it’s more likely that IBS is the underlying issue rather than functional constipation.

Slow Transit Constipation

Have you ever heard someone say they have a “sluggish bowel”? While not everyone who claims this actually has a slow bowel, constipation related to bowel dysmotility is indeed a thing. The exact causes of slow transit constipation remain unclear and are likely influenced by multiple factors. 

One potential cause of slow transit constipation can be an elongated or redundant colon – which is essentially when someone has extra length to their colon, causing more twists for the colon to fit in the abdomen. 

Slow Transit Constipation Symptoms:

The presentation of this subtype is very similar to functional constipation and includes symptoms like:

• Infrequent bowel movements
• Hard, lumpy stools
• Straining
• In some cases, folks who have undergone a colonoscopy and followed the prep instructions meticulously, will still have stool remaining in their bowels

Ultimately, it can be quite challenging to differentiate slow transit constipation from functional constipation simply from symptoms alone. To properly diagnose this subtype of constipation, there are tests that can measure the movement of radioactive markers through the gut over the course of several days.

Pelvic Floor Dysfunction

The pelvic floor is a group of muscles at the bottom of the abdominal cavity. As I’m sure you’ve guessed, the pelvic floor is quite important in regards to constipation. This is because proper coordination of the pelvic floor muscles is key to evacuating the bowels – so let’s start with a little anatomy lesson:

Imagine the pelvic floor as a flexible yet supportive trampoline. Under normal circumstances, it provides stability, keeping everything in place. However, during a bowel movement, the pelvic floor needs to relax and lower, creating space for the rectum to expand and move stool toward the anus. At the same time, the anal sphincter muscles must relax to allow the stool to pass through. This synchronized effort is essential for successful bowel movements. If the pelvic floor doesn’t relax as it should, or if the sphincters fail to coordinate properly, passing stool can become challenging or feel incomplete.

Some people experience dysfunction of the pelvic floor, which can cause various symptoms, including reduced sensation to have a bowel movement, the urge to go without the ability to pass stool, straining, or feeling that stool can only be passed if it’s a specific consistency. Additionally, straining often triggers the opposite effect, causing the pelvic floor to tighten instead of relax, which can further worsen symptoms.

The following symptoms are indicators that issues with your pelvic floor may be contributing to your constipation:

• Straining to pass stool
• Thin stools (may be ‘normal’ consistency, but still difficult to pass)
• Small volume of stool
• Multiple trips to the toilet 
• Fecal incontinence
• Urinary incontinence
• Anal, rectal or vaginal pain or pressure not related to a bowel movement
• Painful intercourse

Medication-Induced Constipation

Constipation can be a side effect of using certain medications – such as opioids and some type of antidepressants, amongst others. I find that it is easy to overlook this subtype, as these types of medications can be so critical to our health. However, it doesn’t mean you have to just “live with the consequences” of the medications that are necessary for your wellbeing. Identifying this subtype can often be addressed by exploring alternative medications or implementing strategies that enhance motility and improve stool consistency.

Constipation from Inadequate Energy Intake

The digestive tract is a series of organs and muscles that require lots of energy to function. In other words – restricting calories or over-exercising can greatly contribute to constipation. If the body is undernourished, digestion can slow down. Therefore, this type of constipation could potentially contribute to the slow transit constipation we reviewed earlier. 

Energy needs are going to vary from individual to individual and it is best to have a dietitian assess your energy needs if you’re not certain. In general, we tend to see that there are certain populations that are at a higher risk for this type of constipation, such as:

• Athletes or those who exercise for long durations or with high intensity
• Those who are restricting their diet for weight loss reasons
• Those who are restricting their diet for other reasons (such as those with GI concerns who avoid eating to reduce symptoms)
• People on weight loss inducing drugs/ medications that suppress appetite

If you have this type of constipation, typical constipation management strategies may help, but a big part of improving your bowel issues will be fixing the root cause. Ie. eating an adequate amount of food each day!

Now What?

Based on the six constipation subtypes above, you probably now have an idea about which type of constipation you’re likely dealing with. But it’s not always a clear answer – you can take my Constipation Quiz to learn more. This is a self-guided Part A & B quiz to get you started on resolving your constipation by asking the right questions!

I also wrote a constipation ebook called Backed Up – which has even more valuable information. Not only do I review the subtypes in detail, but I also review many different management strategies – specifically what can help with each of the different subtypes. 

That said, a more tailored approach is often necessary for those with constipation. In the book, I also provide some insight into key questions and information to provide your doctor so you can get the best care possible for your constipation. Working with a registered dietitian is also highly recommended, as there is no one size fits all diet for those with constipation.