Lower Back Pain When Constipated or Pooping: What You Need To Know

Constipation is a common diagnosis, affecting up to 27% of people in the United States.¹ Certain conditions can cause constipation, and most can be resolved through lifestyle changes and other ways to improve your digestive health.

While constipation is a frequent issue for many, experiencing lower back pain when you’re pooping or while constipated can be worrying. It’s important to know its causes and when to see a doctor for it.

What is constipation, and what causes it?

Constipation is when you have three bowel movements (poops) or fewer per week, and the stool (poop) is often hard, lumpy, and painful to pass. You may also have stomach cramps and feel bloated.

It’s typically caused by your lifestyle, although medical conditions can be the issue in rare cases. The following are some of the many causes of constipation²:

• Not eating enough fiber

• Not drinking enough water

• Not moving enough

• Putting off going to the toilet

• A change in your diet

• Certain medications

• Stress, anxiety, or depression

Medical conditions like an underactive thyroid, irritable bowel syndrome (IBS), or inflammatory bowel disease (IBD) can cause constipation. You’re more likely to suffer from constipation if you’ve had colon surgery or have an injury to your spinal cord or brain.

Bowel obstructions can also cause constipation,³ with other symptoms including pain around your navel (belly button), a hard and swollen belly, inability to pass gas, lack of appetite, and diarrhea. If you have these symptoms, call your doctor immediately.  

What could be causing lower back pain when you have constipation?

Dull lower back pain is a symptom of constipation as the stool in your rectum or colon can cause pressure and discomfort.

It can also be indicative of the following conditions if the pain is more severe:

• Spinal cord injury or tumor

• A compressed nerve in the back

• Parkinson’s disease

• IBS

Other possibilities include liver problems (pain is typically in the upper right abdomen, but it can radiate), kidney infection or stones,⁴ fibromyalgia, and peritonitis. If the pain is severe or there’s blood in your stool, consult your doctor.

Fecal impaction is another potential cause of lower back pain while constipated.⁵ ⁶ It is often accompanied by sudden diarrhea after a long period of constipation, bloating, pain, dehydration, and little to no urine.

Fecal impaction happens more commonly in older people, and it can quickly cause life-threatening issues. If you have dizziness, confusion, a fast or irregular heartbeat, or you’re struggling to breathe alongside any of the above symptoms, call 911 immediately.

What could be causing lower back pain when you have a bowel movement?

Other than constipation and painful, hard stools, there are several other potential causes for experiencing lower back pain while pooping.

Here are three common ones to consider.

Endometriosis

Endometriosis is a common issue if you’ve got a uterus,⁷ ⁸ affecting up to 10% of women worldwide.⁹ This condition occurs when the endometrium (the tissue lining the uterus) attaches to organs and grows outside the uterus. The tissue can attach to the bowel, which can cause pain when passing gas or stool.

There may also be blood in your stool around your menstruation cycle. Speak to your doctor if you have other symptoms, including heavy, painful periods, cramps, pelvic pain, and pain during sexual intercourse. 

Irritable bowel syndrome (IBS)

Studies show that 28 to 81% of people with IBS also have back pain.¹⁰ IBS has many symptoms, but the main ones include bloating, stomachache, constipation or diarrhea, back pain, nausea, and flatulence.¹¹

Stress or certain foods can worsen these symptoms, causing a flare-up. 

Sciatica

Sciatica is another condition that arises from pressure or damage to the sciatic nerve, which runs from the foot to the lower back.¹² Symptoms include dull or sharp pain, a burning sensation, numbness, tingling, or weakness.

These typically affect the lower back or one side of the lower body. If you strain during bowel movements, the pressure can cause lower back pain and other sciatica symptoms. 

How can you treat lower back pain when constipated?

It’s best to treat the root cause of constipation rather than merely apply a band-aid in the form of pain medication or laxatives. However, heating pads and over-the-counter painkillers are helpful when you use them together with gradual lifestyle changes.

To treat constipation, make sure you drink enough water, gradually include more food with plenty of fiber, and stay active. If you’re taking any medication, this may be causing your constipation, so it’s worth discussing this side effect with your doctor.

You can use laxatives or stool softeners as a temporary measure, but you shouldn’t use them for longer than two weeks as they can cause other digestive issues.

When should you see a doctor if you’re experiencing lower back pain because of constipation or bowel movements?

If lower back pain and constipation come on together suddenly, it’s best to see your medical provider, especially if you have other symptoms.

If constipation and lower back pain are chronic issues for you and you’ve tried lifestyle changes with no improvement, you should visit your doctor. There may be an underlying cause.

Even if it’s a typical problem for you, seek medical attention if lower back pain occurs with any of the following symptoms. They indicate something potentially more serious:

• Sharp pains in your back or abdomen

• Fever

• Vomiting

• Blood in your stool or rectal bleeding

Finding blood can be scary, but the cause may not be serious. Bright red blood when you wipe often comes from anal fissures (tears) or hemorrhoids (piles), which are not typically problematic.

However, if you have a lot of pain when sitting or passing stool, bleeding, or notice darker, tarry blood in your stools, it’s best to speak to your doctor.

Many people find talking to a doctor about anything poop-related to be embarrassing, but having an “awkward” consultation could save your life or simply make your life more comfortable. 

The lowdown

Dull lower back pain can occur with constipation. It is worth talking to your doctor if you have any red flag symptoms such as severe pain, blood in your stool, fever, symptoms indicating bowel obstruction, loss of sensation or function of lower limbs, or other concerning symptoms.

You can ease constipation by making lifestyle changes, including drinking more water, being more active, and gradually adding fiber to your diet. Some medications may cause constipation, so speak to your doctor if you’re taking any medicines with that side effect.

Certain conditions like IBS, IBD, and an underactive thyroid can cause constipation, warranting further investigation.

If you’re not constipated but have lower back pain when pooping, this can indicate possible IBS, sciatica, or endometriosis. It’s best to see a doctor if you have symptoms of these conditions so you can learn how to manage them and improve your quality of life.