Sometimes, constipation and low back pain can strike at or around the same time. When this happens, it’s natural to wonder if you have back pain because you’re constipated or if both symptoms are unrelated.
In some cases, constipation can cause lower back pain, and that’s because when you’re constipated, you don’t poo as often or as much as you normally do. The extra poo sitting in your bowels makes them swell up and this can lead to pain in your back.
If you’ve been constipated for a while, it’s also possible for a dry hard lump of poo to get stuck and block your bowels. This is known as faecal impaction and can also cause back pain.
But this doesn’t always happen, which means that you shouldn’t assume constipation is giving you back pain if both happen at the same time. Something else may be to blame.
Causes of constipation and back pain
There are several reasons why you may have constipation and low back pain at the same time.
- Being constipated is giving you low back pain.
- You have a medical condition that causes both constipation and low back pain.
- Different things are causing your low back pain and constipation.
Why being constipated can cause back pain
You’re probably constipated if:
- your poo is hard, dry, large or lumpy
- you’ve not had a poo at least 3 times over the last 7 days
- you have to strain or it hurts when you poo
And when this happens, you usually have a lot of poo in your bowels, which - as mentioned above - can cause back pain. If you’ve been constipated for a while, you can develop faecal impaction (when a hard lump of poo gets stuck in your bowels and blocks more poo from passing) which can also cause low back pain.
Back pain caused by constipation usually feels like a dull ache and it should go away once you starting pooing normally again.
But if the pain is from faecal impaction, you should see a doctor immediately as this can cause serious complications.
You may have faecal impaction if you have the following symptoms:
- tummy pain, bloating or discomfort
- leaking soft poo
- feeling or being sick
- feeling the need to push
- headache and loss of appetite
- losing weight without meaning to
Medical conditions that cause back pain and constipation
Sometimes a medical condition can cause constipation and back pain. Examples of such conditions include:
- bowel obstruction
- inflammatory bowel disease (IBD)
- irritable bowel syndrome (IBS)
- fibromyalgia
- endometriosis
Being pregnant can also cause low back pain and constipation because of changes in your levels of certain hormones, loosening of the ligaments in your body and the effect of carrying extra weight on your body.
Separate causes of back pain and constipation
While low back pain and constipation are sometimes related, both can also happen at the same time - purely by chance. They’re both common conditions.
Constipation can be caused by many things, including your diet, not doing enough exercise, certain medications and some medical conditions.
Low back pain also has many causes, such as a muscle injury and medical conditions, like sciatica or a slipped disc. However, most cases of back pain have no clear cause and they get better on their own with time.
Read more about the causes of low back pain and causes of constipation.
Even though low back pain and constipation are common and usually not caused by anything serious, they can sometimes be a sign of a condition that needs urgent medical care.
Find out when to see a doctor about constipation and when to take medical action about back pain.
Key points
- constipation and low back pain are both common
- constipation can cause low back pain because of a build up of poo in the bowel or a piece of poo getting stuck and blocking the bowel
- constipation and low back pain can also happen at the same time because of an underlying condition like irritable bowel syndrome
- both conditions can also happen at the same time, purely by chance
