Pain in the left side of the back – causes and treatment

20th November, 2020 • 8 min read

There are many potential causes for pain in the left side of your back. It could be a result of muscular or bone pain, for example, or the result of an injury.

Your back is made up of many bones arranged in the spinal column – your spine. This provides support for your body and allows you to stand, sit and move around.

Your back also includes muscles, ligaments and nerves. These can sometimes be affected by a strain, injury or inflammation because of the amount of wear and tear you place on your back every day.

It's also possible to injure your back if you hurt it in a fall or playing sport.

But back pain is very common and pain in the left side of the back is not unusual.

Another potential cause of pain in the left side of your back is inflammation or infection of the internal organs in that area.

For example, kidney stones can cause pain in the lower back. But in these cases, you would often experience other symptoms in addition to back pain.

Here we'll look at what might be causing back pain in the left side and some of the most common symptoms.

Left side back pain and your muscles

Muscle strains are a common cause of back pain, including left side back pain.

You may have strained yourself while working out in the gym or on the football pitch. Perhaps you have moved awkwardly while getting out of bed in the morning.

Bad posture is another cause of pain in the back or side. If you often sit or stand in a poor position, it may place added stress on your muscles and your spine.

Left side back pain and your spine

As we get older, wear and tear on our bones can also cause pain.

One common back issue is a

slipped disc
, which happens when the cushioning rings of the spine are pushed out of place. This means that the disc presses onto the spinal nerves, causing pain.

If you have a condition such as

, this can also cause pain down the left side of your body.

Left side back pain and internal organs

Even though you might feel that the pain may be coming from your back, pain in your side might actually be coming from the organs in your tummy or pelvis.

The kidneys, pancreas, colon and uterus are all located in the lower part of the trunk of your body.

Kidney stones
, for example, can cause pain in the left side of your back.

Pancreatitis can also cause back pain, as well as an abdominal aortic aneurysm, which is when a bulge or swelling forms in the main blood vessel that runs from your heart down to your tummy, known as the aorta.

If any of your organs are affected, there’s a good chance that you will be feeling ill with other symptoms aside from the back pain. This could be a temperature, fever, nausea, shortness of breath or pain when passing pee, as well as a range of other symptoms, depending on the cause.

If you're feeling unwell with any of these or other symptoms, you should see a doctor.

How to relieve left side back pain

There are lots of ways you can reduce back pain and help the recovery yourself at home:

  • try gentle activities, such as a yoga or pilates class, a short walk or swimming
  • take extra care when lifting or moving heavy objects
  • try to keep as active as possible, as resting for long periods may make the symptoms worse
  • use hot and cold compression packs. These are available in pharmacies, or simply use a hot water bottle and a bag of frozen ice wrapped in a towel
  • use an anti-inflammatory cream to rub onto the sore part of your body or it may help to take a painkiller. Speak to your pharmacist or doctor for further guidance on how to safely get and use these medicines
  • if your back is sore at night, try using a pillow either between or under your knees to help support the back

With some extra care and attention, the pain should get better on its own. If the pain persists, though,

see a doctor

When to seek medical help for left side back pain

Back pain, even in one side, will usually improve within a few weeks.

However, if you're very uncomfortable and the pain doesn’t seem to be going away, or it’s stopping you from getting on with your daily activities, it's best to see a doctor or health practitioner.

Red flags and worrying symptoms

You should seek medical help immediately if you have back pain and also have:

  • chest pain
  • a high temperature
  • unintentional weight loss
  • numbness or tingling around your genitals or buttocks
  • difficulty peeing
  • loss of bladder or bowel control – peeing or pooing yourself
  • a swelling or a deformity in your back
  • if the pain is coming from the top of your back, between your shoulders, rather than your lower back
  • if your pain started after a serious accident, such as a car accident
  • if your pain does not improve after resting or is worse at night
  • if your pain is so bad you're having problems sleeping
  • if your pain is made worse when sneezing, coughing or pooing

These symptoms could be a sign of something more serious and need to be checked urgently. It's also a good idea to see your doctor if:

  • the pain is very severe or gets worse over time
  • you're worried about the pain or struggling to cope
  • the pain does not start to improve within a few weeks
  • the pain stops you from doing your day-to-day activities

If you don't have these symptoms, but are concerned or uncomfortable due to your back pain, you should still see a doctor. They will be able to discuss your symptoms and talk to you about treatment options.

These might include self-help techniques, such as low-impact

exercises to do at home
. You might be referred to a specialist, such as a physiotherapist, for further tests and care.

Your doctor may decide to offer you medication, such as an

anti-inflammatory medicine
, such as non-steroidal anti-inflammatory (NSAID) tablets . Your doctor will tell you how to safely get and use this.

Key points

  • back pain is very common and feeling pain in one side of the back is not unusual
  • a common cause of back pain in 1 side is a minor injury to the muscles
  • occasionally, the pain may be caused by your internal organs or pelvis
  • there are lots of ways you can reduce back pain and help the recovery process yourself at home
  • if you are very uncomfortable or the pain doesn’t go away on its own, it's best to book an appointment with a doctor

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.