Quick answer: Yes, constipation can cause back pain, but less often than people assume. A buildup of stool can press on nerves in the lower spine and cause a dull, achy lower-back pressure. The best clue is that it eases after a bowel movement. Often, though, something else is behind both, such as IBS, pain medicines or inactivity. Back pain with numbness around your bottom, or loss of bowel or bladder control, is an emergency.
Lower back pain and constipation are both common, so plenty of people have them at the same time. The real question is whether one is causing the other. That matters, because the fix is different. Stretching won't empty a backed-up colon, and a laxative won't fix a slipped disc.
This guide explains how constipation can cause back pain, how back problems can cause constipation, the red flags you shouldn't wait on, and a simple log that helps you tell them apart.
Key takeaways
- A large amount of stool in the colon can press on nerves in the lower spine and cause back pain [1].
- Constipation-related back pain is usually a dull, achy pressure that improves after a bowel movement [1].
- The link often runs the other way. Back pain leads to pain medicines and less movement, and both can cause constipation [1][2].
- Numbness in the buttocks or inner thighs, or loss of bowel or bladder control, with back pain needs emergency care [3].
- Logging pain scores before and after bowel movements for 1–2 weeks is a practical way to see whether they're linked.
Can constipation cause back pain?
Sometimes. Cleveland Clinic explains that a large amount of stool in the colon can put pressure on nerves in the lower spine [1]. A more severe version, fecal impaction, is a hard mass of stool stuck in the rectum. It can also cause back pain and needs prompt treatment [1].
More often, though, Cleveland Clinic notes that a shared condition causes both symptoms [1]. Examples include:
- IBS. It can amplify pain signals, and gut pain can be felt as back pain [1].
- Neurologic conditions such as Parkinson's disease and multiple sclerosis, which can affect both gut movement and the back [1]
- Tumors pressing on the spine or crowding the lower abdomen [1]. These are uncommon, but they're why persistent symptoms need checking.
- Endometriosis, which can cause lower tummy and back pain, and pain when you poop [4]
Where is constipation pain felt?
Usually in the lower belly, often on the left, with fullness, cramping or bloating. Sometimes it's felt as a dull ache across the lower back.
| Feature | More likely constipation-related | More likely a back (musculoskeletal) problem |
|---|---|---|
| Feel | Dull, achy pressure [1] | Sharp, catching, or worse with certain movements [1] |
| Timing | Builds over no-go days | Linked to lifting, posture or a specific strain |
| After a bowel movement | Eases [1] | Unchanged |
| Moving around | Not much effect | Worse with movement [1] |
| Other clues | Hard stools, straining, bloating | Stiffness, pain into a leg |
A pattern isn't a diagnosis. Pain can also come from the kidneys, the pelvis or elsewhere. If you're not sure how to put it into words for a doctor, see how to describe abdominal pain.
Can back pain make you constipated?
Yes, indirectly, and this direction may be more common.
- Pain medicines. Narcotic (opioid) pain medicines are a well-known cause of constipation [2]. Cleveland Clinic also lists muscle relaxants among back-pain treatments that can constipate [1].
- Less movement. Back pain limits activity, and too little physical activity is a listed cause of constipation [2].
- Avoiding the toilet. If sitting or straining hurts, people put off going. Ignoring the urge to have a bowel movement is itself a cause of constipation [2].
If constipation started when you began a new pain medicine, tell your prescriber. Don't stop a prescribed medicine on your own [7].
Back pain and constipation red flags
Some combinations need urgent care.
Go to the emergency room now if you have back pain with:
- Numbness or tingling in your buttocks, inner thighs or the backs of your legs
- New loss of bowel or bladder control, or difficulty passing urine
- New leg weakness
These can be signs of cauda equina syndrome, a compression of nerves at the base of the spine that Cleveland Clinic calls a medical emergency [3].
Also seek urgent care for constipation with:
- Vomiting, a swollen belly, crampy pain and being unable to pass gas, which are possible bowel obstruction signs [5]
- Watery leakage after days without a proper bowel movement, which can be fecal impaction with overflow [6]
See a doctor right away if constipation comes with rectal bleeding, blood in the stool, constant belly pain, fever, unintended weight loss or lower back pain. NIDDK lists all of these as reasons to see a doctor promptly [2]. Back pain and constipation lasting more than a few weeks also deserve a check [1].
How to tell from your log
The most useful single question is: does the back pain ease after a bowel movement? Track it for one to two weeks.
- Rate back pain (0–10) when you wake, and again within an hour after each bowel movement.
- Log each bowel movement with its Bristol type and whether you strained.
- Note no-go days, pain medicines (name and time) and activity (walked / mostly sitting).
Illustrative example: a week of back pain vs. bowel movements
This is an illustrative example, not real user data.
| Day | BM? | Bristol type | Back pain on waking | Back pain after BM | Notes |
|---|---|---|---|---|---|
| Mon | No | — | 3 | — | Desk day |
| Tue | No | — | 4 | — | Bloated |
| Wed | Yes | 1 | 5 | 2 | Strained; ache eased within an hour |
| Thu | Yes | 3 | 2 | 1 | Walked 30 min |
| Fri | No | — | 3 | — | Took ibuprofen |
| Sat | Yes | 2 | 4 | 2 | — |
| Sun | Yes | 4 | 1 | 1 | — |
Reading it: in this invented example, pain and bowel movements varied together. That does not determine whether constipation, a back problem or another condition explains the pain. Describe the timing and any movement-related changes to a clinician.
Our constipation diary guide explains how to record bowel observations and accompanying symptoms.
What helps when constipation is causing the back pain?
Treatments depend on the cause of the pain. Do not assume constipation explains back pain or that treating it will relieve the ache. NIDDK's first steps [7]:
- Add fiber gradually and drink plenty of fluids
- Get regular physical activity. Gentle walking can help your back and your bowels.
- Try for a bowel movement at the same time daily, 15–45 minutes after breakfast, and go when you feel the urge
- A footstool under your feet on the toilet can help straighten the anorectal angle [8]
If those don't help, ask your doctor or pharmacist about laxatives. If you take opioid pain medicines, ask your prescriber how to prevent constipation alongside them.
How to track this
Back pain and bowel habits are easy to misremember, especially across a week. Record:
- Every bowel movement with Bristol type and straining
- Back pain scores before and after bowel movements
- Pain medicines and activity
- No-go days
For ongoing records, explore the Get Regular poop tracker. Compare the current logging workflow and access with the details you want to keep. An app record does not identify the cause of a bowel change.
When to see a doctor
Emergency: back pain with numbness around the buttocks or inner thighs, loss of bowel or bladder control, or leg weakness [3]. Constipation with vomiting, swelling and no gas [5].
See a doctor soon if you have:
- Blood in or on your stool, or black, tarry stool
- Unintended weight loss or fever [2]
- New constipation, especially if you're over 50
- Constipation alternating with thin stools
- Back pain and constipation lasting more than a few weeks [1]
- A family history of colon or rectal cancer [2]
See our full checklist: when to see a doctor about bowel changes. If nausea is part of it, read can constipation cause nausea. If you've gone several days without a bowel movement, see haven't pooped in days.
FAQ
Can constipation cause lower back pain on the left side?
Constipation pain is often felt in the lower left belly, and stool buildup can cause a dull lower-back ache [1]. Side alone can't tell you the cause. One-sided pain with fever or urinary symptoms needs a doctor, because kidney problems can feel similar.
How do I know if my back pain is from constipation?
The strongest clue is that the pain eases after a good bowel movement [1]. Log pain before and after bowel movements for a week or two and look for that pattern.
Can a herniated disc cause constipation?
Back problems can lead to constipation indirectly, through pain medicines, less movement and putting off the toilet [1][2]. A disc pressing on the nerves at the base of the spine can cause cauda equina syndrome. Any new loss of bowel or bladder control with back pain is an emergency [3].
Will a laxative help back pain from constipation?
If constipation is the cause, relieving it may ease the ache. Start with fiber, fluids, activity and a regular toilet routine [7]. Ask a pharmacist or doctor before using laxatives regularly.
Sources
- Cleveland Clinic Health Essentials. Can Constipation Cause Back Pain? How To Know. https://health.clevelandclinic.org/can-constipation-cause-back-pain
- NIDDK. Symptoms & Causes of Constipation. https://www.niddk.nih.gov/health-information/digestive-diseases/constipation/symptoms-causes
- Cleveland Clinic. Cauda Equina Syndrome. https://my.clevelandclinic.org/health/diseases/22132-cauda-equina-syndrome
- NHS. Endometriosis. https://www.nhs.uk/conditions/endometriosis/
- Cleveland Clinic. Changes in Bowel Habits. https://my.clevelandclinic.org/health/symptoms/changes-in-bowel-habits
- Cancer Research UK. Chronic constipation and faecal impaction. https://www.cancerresearchuk.org/about-cancer/coping/physically/bowel-problems/types/chronic-constipation
- NIDDK. Treatment for Constipation. https://www.niddk.nih.gov/health-information/digestive-diseases/constipation/treatment
- Sadler K, Arnold F, Dean S. Chronic Constipation in Adults. Am Fam Physician. 2022;106(3):299–306. https://www.aafp.org/pubs/afp/issues/2022/0900/chronic-constipation-adults.html
This article is for general education and isn't medical advice. Get Regular is a tracking app — it doesn't diagnose or treat any condition. If you have red-flag symptoms or ongoing changes in your digestion, talk to a doctor.