Pain on left side of stomach – what could be causing it

1st July, 2020 • 5 min read

Having a pain or ache in the left side of your stomach can be really uncomfortable and worrying too.

Left-side abdominal pain is a common problem but can be difficult to diagnose as there are several important organs in this area, including the spleen, stomach and left kidney. A range of digestive issues could also be to blame.

What digestive conditions could be causing the pain?

Constipation, IBS and Gastroenteritis

Left side of stomach pain can be a sign that there’s something wrong with your digestive system.

Aching or cramping can be linked to constipation, irritable bowel syndrome (IBS) or gastroenteritis, where the lining of your stomach or small intestine is irritated or becomes inflamed.

Short-term digestive issues like constipation or gastroenteritis can be treated from home, but it’s important to monitor your symptoms and visit a doctor if the pain doesn’t settle.

IBS, constipation and gastroenteritis can also cause pain in the right side of your abdomen.


If the pouches in the wall of your small and large intestine get infected, this can cause a condition known as diverticulitis, which causes constant abdominal pain on left side in a lower area, as well as high fever, diarrhea, nausea or vomiting or blood in your stools.

Intermittent, crampy pain towards the left of your tummy can also be a symptom of diverticulosis.

You may also notice that your pain seems to flare up while you’re eating, or just after you’ve finished a meal.

The condition is fairly common in western countries - affecting approximately 50% of people over the age of 50 - and may be linked to a lack of dietary fibre.

It’s usually harmless and some people don't experience any symptoms, but some people with diverticulosis feel a constant, dull ache towards the lower left side of the stomach.

If you think that you might have a chronic condition like diverticulosis, see a doctor. Treatment can vary depending on the severity of your symptoms, but a diet that’s rich in high-fibre foods like wholemeal bread, beans and brown rice may help.

Could the pain be a sign of kidney conditions?

Kidney infection

Left side stomach pain can be a sign that your left kidney is infected.

Kidney infections normally develop when a bacterial infection travels from your bladder to your kidneys and this can cause dull, aching pain towards the left of your abdomen.

Other symptoms include pain in your lower back or groin, nausea, and a fever. You may also notice some blood in your pee.

If you have lasting abdominal pain and a fever, see a doctor. Most kidney infections can be treated with antibiotics, but can cause permanent damage to your kidneys if left untreated.

Kidney stones

Kidney stones develop when waste products like calcium form crystals in your kidney. Small stones can sometimes pass in your pee, but larger stones will need to be removed so that they don’t cause permanent damage to your kidney.

Kidney stones can also cause left-sided abdominal pain, but the type or ‘character’ of the pain tends to be different. People with kidney stones often experience a severe, stabbing pain in the back or tummy, and it is not unusual for this pain to come and go in spasms.

If you have a kidney stone, you may also find that you feel sweaty and sick, or notice that there’s some blood in your pee.

If you think you might have kidney stones, see a doctor. While you wait for medical help, drink plenty of hydrating fluids and take a painkiller if necessary to manage the pain.

Could I have a swollen or damaged spleen?

Occasionally, pain in left side of abdomen can be a sign that something is wrong with your spleen.

The spleen is a small, fist-sized organ located just underneath your stomach. It helps to filter your blood and create new blood cells.

Your spleen may hurt if it’s damaged or ruptured in an accident, or it can become swollen and painful as a result of a condition like leukemia or rheumatoid arthritis.

Other signs that your spleen has become swollen or damaged include:

  • pain or tenderness behind your ribs
  • dizziness and rapid heart rate
  • feeling full very quickly after eating (because your spleen is pressing against your stomach)
  • frequent infections
  • fatigue

If you think that your spleen may be damaged or swollen, you should go to your nearest hospital immediately. They may organise scans and tests to find the cause, and may be able to prescribe medication to treat the underlying cause.

Read more about how to tell if your stomach pain is serious.

When to see a doctor

If you think the pain on the left side of your abdomen could be caused by any of the conditions above, you should see a doctor.

You should also contact a doctor if you have left side of abdomen pain and you:

  • are pregnant
  • experience persistent sickness or vomiting
  • are bringing up blood, or see blood in your poo
  • have persistent diarrhea
  • have recently lost a lot of weight without trying to
  • feel breathless or light-headed

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.