Ulcerative colitis

The main symptoms of ulcerative colitis are:

• recurring diarrhoea, which may contain blood, mucus or pus
• tummy pain
• needing to poo frequently

You may also experience extreme tiredness (fatigue), loss of appetite and weight loss.

The severity of the symptoms varies, depending on how much of the rectum and colon is inflamed and how severe the inflammation is.

For some people, the condition has a significant impact on their everyday lives.

Ulcerative colitis is thought to be an autoimmune condition.

This means the immune system, the body's defence against infection, goes wrong and attacks healthy tissue.

The most popular theory is that the immune system mistakes harmless bacteria inside the colon as a threat and attacks the tissues of the colon, causing it to become inflamed.

Exactly what causes the immune system to behave in this way is unclear.

Many experts think it's a combination of genetic and environmental factors.

Treatment for ulcerative colitis aims to relieve symptoms during a flare-up and prevent symptoms from returning (maintaining remission).

In most people, this is achieved by taking medicine, such as:

• aminosalicylates (ASAs)
• corticosteroids (steroid medicines)
• immunosuppressants

Mild to moderate flare-ups can usually be treated at home. But more severe flare-ups need to be treated in hospital.

If medicines are not effective at controlling your symptoms or your quality of life is significantly affected by your condition, surgery to remove some or all of your bowel (colon) may be an option.

During surgery, your small intestine can be diverted out of an opening in your abdomen known as a stoma. This type of surgery is known as an ileostomy.

In some cases, the stoma is only temporary and can be closed up once your bowel has healed.

An alternative option is to create an internal pouch that's connected to your anus called an ileoanal pouch.

Read more about treating ulcerative colitis

Common symptoms of ulcerative colitis include frequent diarrhoea (which may be bloody), stomach aches and needing to go to the toilet a lot.

Ulcerative colitis is usually treated with medicines that reduce the inflammation in your digestive system. Surgery may be needed in severe cases.

It's not clear what causes ulcerative colitis. A possible cause is your immune system attacking your digestive system.