Feeling and being sick

Feeling sick (nausea) and being sick (vomiting) are very common if you have pancreatic cancer.

What's in the 'Feeling and being sick' section?

Feeling and being sick can be caused by the cancer or be a side effect of treatment. It can also be a symptom of pancreatic cancer before it’s diagnosed. Read more about symptoms.

Speak to your GP, doctor or nurse if you have nausea or vomiting. It’s not something you have to put up with. There are effective anti-sickness (anti-emetic) medicines that can help. Some people also find other things such as ginger, peppermint or complementary therapies helpful.

Feeling and being sick is unpleasant and distressing. It may also mean that you are not properly absorbing medicines that you take as tablets, including pancreatic enzyme replacement therapy (PERT).

Persistent vomiting

If you are being sick a lot (persistent vomiting), and are struggling to keep down any food or fluid, this can be a sign that something is wrong. It can lead to dehydration (where your body loses more water than it takes in) and your body may not get the nutrition it needs.

Contact your GP or medical team if you have been vomiting for half a day or longer and can’t keep down any food or fluid or have symptoms of dehydration. You could also call 111.

You may need to go to hospital, where they will work out the cause of the vomiting. You may need to be given fluid through a drip into a vein to treat dehydration.

What causes sickness?

There are a few things that can cause sickness if you have pancreatic cancer.

Blocked duodenum

The cancer can block the duodenum, which is the first part of the small intestine. You can see the duodenum on this diagram. The blockage can stop food passing out of the stomach into the duodenum. The food builds up in your stomach and makes you feel and be sick.

If you are having long term treatment and are well enough, you may have bypass surgery to treat the blockage. This is an operation that connects the stomach to the small intestine below the blockage, so food can pass through. This should stop the sickness. Or you may have a hollow tube called a stent put in to open up the blockage and stop the sickness.

If you have a blocked duodenum, your doctor will talk to you about the best treatment for you.

Stomach emptying slowly

Pancreatic cancer can affect the nerves and hormones that control the stomach. If this happens, food passes through the stomach more slowly. This is called delayed gastric emptying or gastroparesis. It can make you feel full all the time and feel sick . It can also cause other problems like indigestion (a painful, burning feeling in your chest) and difficulty finishing even small meals. Medicines such as steroids and certain types of anti-sickness medicine can help.


The cancer can block the bile duct. This is the tube that takes a fluid called bile from the liver to the duodenum (the first part of the small intestine). You can see the bile duct on this diagram.

This causes jaundice, which can make you feel and be sick, as well as turning your eyes and skin yellow. A hollow tube called a stent may be put in to open up the blockage. This should treat the jaundice and stop the sickness.

Some treatments for the cancer

Some treatments for the cancer, such as chemotherapy or radiotherapy, can make you feel sick. You should be given anti-sickness medicine to help with this.

You may also feel sick after having surgery to remove the cancer. This is because it can take time for your digestive system to start working properly again. The sickness can be treated with drugs and is usually only temporary. Eating smaller meals more often can also help.

Problems digesting food

Pancreatic cancer can cause problems with digesting food, which can make you feel sick. Problems digesting food can be treated with pancreatic enzyme replacement therapy (PERT), which should relieve sickness. Read more about digestion and pancreatic cancer.

Some medicines

Some medicines such as antibiotics and opioid painkillers (for example, morphine) can make you feel sick. Follow the advice your medical team give you about how to take your medicines, as this will help to prevent sickness. This includes instructions about taking tablets with or after food. Your doctor or nurse may also give you anti-sickness medicine.

Opioid painkillers can cause constipation (when you find it harder to poo), which can cause sickness, as well as being very uncomfortable. You should be given medicines called laxatives to take with opioids. If these don’t help, speak to your nurse or doctor.


Feeling anxious or distressed can make you feel sick. For example, people sometimes feel sick because they feel anxious before chemotherapy treatment.

There are things that can help with anxiety. Your doctor or nurse may give you a medicine to treat anxiety, such as lorazepam. Or you might find relaxation techniques can help. Read about different ways to help you deal with the emotional impact of pancreatic cancer.

Symptoms towards the end of life

Feeling and being sick can also be a symptom towards the end of life.

Read more about sickness towards the end of life.

Read our fact sheet about feeling and being sick

To read about feeling and being sick, what causes it, and what can help, download our fact sheet, Feeling and being sick.

Download our fact sheet
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“My dad found sucking sweets helped with the bile taste in his mouth which made him feel very sick and prevented him eating at times.”

References and acknowledgements


If you would like the references to the sources used to write this information, email us at publications@pancreaticcancer.org.uk


We would like to thank the following people who reviewed our information on feeling and being sick.

  • Adele Hug, Specialist Oncology Dietitian
  • Chloé McMurray, Senior HPB Dietitian – Nutrition & Dietetics, North Tees and Hartlepool NHS Foundation Trust
  • Dan Monnery, Consultant in Palliative Medicine, The Clatterbridge Cancer Centre NHS Foundation Trust
  • Emma Westmancoat, HPB Clinical Lead Dietitian, Department of Dietetics & Nutrition, Queens Medical Centre, Nottingham University Hospitals NHS Trust
  • Karen McAdam, Consultant Medical Oncologist
  • Pancreatic Cancer UK Information Volunteers
  • Pancreatic Cancer UK Specialist Nurses

Published June 2022

To be reviewed June 2025