At least 1 in every 227 people in the UK has been diagnosed with ulcerative colitis. We discuss what this bowel condition is to help you identify the signs & symptoms to look out for

What is ulcerative colitis?

Ulcerative colitis is a form of inflammatory bowel disease (IBD) that causes the colon (large intestine/bowel) and rectum (end of the large intestine/bowel) to become inflamed. IBD is not the same as irritable bowel syndrome (IBS). Although they may share some similar symptoms, the treatment is not the same. If you’re struggling to determine whether you have a form of IBD or IBS, consult with your GP.

Ulcerative colitis is a long-term condition, commonly diagnosed in people before the age of 30. However, it can affect people of all ages. When the colon becomes inflamed, sores or ulcers develop which can bleed and produce pus.

There are three different types of colitis that are based on how much of your colon is affected, including:

• Proctitis – where bowel inflammation is limited to the rectum

• Left-sided colitis – where bowel inflammation begins at the rectum and extends up to the left side of the colon also known as descending colon

• Total colitis – Also known as pancolitis. This form affects the entire colon

What are the main causes of ulcerative colitis?

Although the exact cause of ulcerative colitis is unknown, it’s thought to develop from problems within the immune system. Some of the likely causes include:


The genes you inherit may be a contributing factor to your ulcerative colitis. Therefore, if a close relative has the condition, it increases your chances of developing it too. It’s thought that there are many genes that can increase someone’s chances of getting ulcerative colitis, some of which control the immune system.

Autoimmune condition:

Some people believe that ulcerative colitis is an autoimmune condition, where your immune system mistakenly attacks the healthy cells of your organs and tissues, resulting in inflammation of the colon and rectum.

Environmental factors:

It’s thought that various environmental factors can increase the likelihood of ulcerative colitis developing, such as viruses, bacteria, specific diets, air pollution, daily stress, medicine and smoking. However, there is no specific evidence that confirms these factors are causes of ulcerative colitis.

Gut flora:

Those with ulcerative colitis are thought to have fewer varieties of ‘friendly bacteria’ in their gut than people who don’t have the condition. Therefore, some of the bacteria, viruses and fungi that aid the gut are missing and can trigger symptoms to flare up.

What are the signs & symptoms of ulcerative colitis?

Symptoms of ulcerative colitis will differ from person to person and can range in severity depending on where the colitis is active in your bowel and how severe the inflammation is. For some, the symptoms of colitis can significantly impact their daily activities. Symptoms are also likely to change over time.

The most common symptoms include:

• Diarrhoea that keeps returning (you may notice your poo contains mucus or blood)

• Extreme tiredness

• Weight loss

• Loss of appetite

• A sudden urge to go to the toilet more frequently

• Pain in your tummy, particularly when you need to go to the toilet


• Bleeding from your anus

Some people can experience no symptoms for a period of time, this is known as ‘remission’. Others will experience mild symptoms that can prolong for weeks or months, followed by flare-ups where symptoms accelerate and become more challenging to manage.

• Mouth ulcers

• Painful and swollen joints (arthritis)

• Red, irritated eyes

• Health conditions that weaken bones, including osteoporosis

•  Swollen fat under the skin, known as erythema nodosum

Although it’s hard to pinpoint the cause of a flare-up, they’re often associated with a gut infection or stress.

If you’re experiencing any of the symptoms above and are concerned, speak to your GP.

Can you get rid of ulcerative colitis?

Although there’s currently no cure for ulcerative colitis, there are plenty of treatment options available that aim to stop inflammation of the bowel and help reduce symptoms (induce and maintain remission).

Treatment can be provided by several healthcare professionals known as your ‘care team’, including gastroenterologists (a doctor who specialises in treating digestive disorders), surgeons, specialist nurses and your GP. These are the people who will co-ordinate your care and the people you’ll contact if you need advice.

The following treatments for ulcerative colitis include:

• Aminosalicylates – this medicine, also known as 5-ASAs, helps reduce inflammation and is usually the first line treatment option for mild to moderate ulcerative colitis

• Corticosteroids – these are an alternative type of medicine used to reduce inflammation. These are used to treat a flare-up and can be used alone or with 5-ASAs

• Immunosuppressants – medicines that reduce the activity of the immune system. Although they can be a very effective treatment option, they can take some time before they start to work

Like all medicines, the ones mentioned above each have side effects to be aware of. Your GP or care team will discuss these with you.

Severe flare-ups can be more challenging to treat at home. It’s likely that a severe flare-up will be managed in hospital. This helps your care team monitor your condition, whilst helping to minimise risks of dehydration and other complications.

The medicine you’ll be given in hospital can sometimes be administered directly into a vein (intravenously). Some of these medicines include:

• Ciclosporin – continuously given slowly through a drip in your arm (infusion) for around seven days

• Biologic medicines – help reduce inflammation of the intestine and are given through a drip in your arm every four to 12 weeks or as an injection every one to four weeks

• JAK inhibitors – new types of medicines that work by blocking enzymes (proteins) that the immune system uses to trigger inflammation

• Ozanimod – a tablet that you take once a day. This is a preferred option when standard treatments or biologic medicines have not worked or are not suitable

When frequent flare-ups can’t be treated with medicines and start to have a significant impact on your daily life, surgery may be an option to discuss with your GP or care team. Surgery would involve permanently removing the colon, called a colectomy. Removing the colon directs the passing of waste products to your small intestine. Once the colon is removed, ulcerative colitis cannot come back.

Surgery of this degree is something your care team will discuss with you to determine whether this is the best option for you.

Can some foods bring on a flare-up?

There isn’t any clear evidence that specific foods cause or trigger the inflammation in Colitis. The most important thing you can do is try to eat a nutritious and balanced diet and to drink plenty of fluids.

The symptoms of ulcerative colitis differ from person to person. Some people may notice certain foods trigger a flare-up. To help identify which foods do this, it can be a good idea to keep a food diary. You can use it to document the foods your body can tolerate and the ones that make symptoms worse.

Although there isn’t a one-size-fits-all diet that can assist ulcerative colitis, there are some adjustments you can make to your diet to help you better manage your condition, including:

• Portion control – eat smaller, more frequent meals throughout the day may help manage your symptoms. Need help? Read our food portions guide

• Eating foods that are part of a low-residue diet (a diet which contains little or no fibre/roughage). Always talk to your GP or care team before doing this to assess your suitability

• Drink plenty of fluids – check out our practical tips to help you drink more water

• Ask your GP for advice on food supplements – these can help if you’re not getting enough vitamins and minerals into your daily diet

Before you plan to make changes to your diet you should always consult with your GP or care team first.

How does ulcerative colitis differ from Crohn’s disease?

Ulcerative colitis can often be mistaken for Crohn's disease as both conditions cause inflammation of the gut and painful sores. Plus, they are both a form of Irritable Bowel Disease (IBD) but what’s the difference between the two?

Unlike ulcerative colitis, Crohn’s disease describes inflammation anywhere in the gut. This can be from your mouth to your anus. Whereas ulcerative colitis only affects the large bowel.

Both are life-long conditions that can be effectively managed with the right treatment. If you’re unsure whether your symptoms relate to ulcerative colitis or Crohn’s disease, speak to your GP.

When should I see a doctor about ulcerative colitis?

If you’re experiencing symptoms of ulcerative colitis and haven’t yet determined a diagnosis, you must consult your GP as soon as possible. They will ask about your symptoms, physically examine you and conduct some tests, such as a blood test, to check for inflammation in your body.

If your GP suspects that you may have ulcerative colitis, they’ll likely refer you to hospital for further testing. Try not to worry at this stage as this is a normal procedure and can bring you one step closer to a confident diagnosis.

Some of the hospital tests you may be referred for can include a CT scan or an X-ray. This gives your healthcare professional a more detailed examination of your rectum and colon. Other tests include:

• A sigmoidoscopy – where a thin, flexible tube containing a camera is inserted into your rectum (bottom)

• A colonoscopy – used by healthcare professionals if they think your ulcerative colitis has affected more of your colon. This test uses a flexible tube containing a camera to examine the entire colon

Alternatively, if you’ve already been diagnosed with ulcerative colitis and think you’re experiencing a severe flare-up, you should contact your GP or care team for further advice.

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