Managing diabetes if you have pancreatic cancer

Diabetes is a condition where the amount of sugar in your blood (blood sugar level) is too high. The pancreas plays an important role in controlling your blood sugar level.

When you digest food and drink, carbohydrates are broken down into glucose, which is a type of sugar. Glucose passes into your blood and is used by the body. Your pancreas makes hormones called insulin and glucagon, which help to control the amount of glucose in your blood.

If you have pancreatic cancer or you have had surgery to remove all or part of your pancreas, your pancreas may not make enough insulin or glucagon. This can mean that your blood sugar levels are not controlled properly. Diabetes is a condition where the amount of sugar in your blood is too high.

Diabetes can also be a symptom of pancreatic cancer before you are diagnosed – read more about symptoms of pancreatic cancer.

A high blood sugar level is called hyperglycaemia. It can make you lose weight, feel very thirsty, need to pass urine (pee) more often, get headaches and feel tired. Your blood sugar level can also become too low. This is called hypoglycaemia, it can make you feel hungry, shaky or sweaty.

The coronavirus (COVID-19) can cause more severe symptoms and complications in people with diabetes. If you have diabetes and you have symptoms of coronavirus, contact your diabetes nurse, hospital team or GP for advice about your diabetes medicine. We have more information about the coronavirus for people with pancreatic cancer. Diabetes UK have information about diabetes and coronavirus.

Managing diabetes

Pancreatic cancer can make managing diabetes difficult. If you are diagnosed with diabetes, you should see a specialist dietitian. If you haven’t seen a specialist dietitian, ask your doctor or nurse to refer you to one. You may also see a diabetes nurse for help with managing any medicine you are given.

Your dietitian or diabetes nurse will help you control your blood sugar levels. You may need to monitor your blood sugar level regularly, and take tablets or have insulin injections to control it.

If you already had diabetes before you were diagnosed with pancreatic cancer, the cancer may make your diabetes more difficult to control. Your diabetes team may need to make changes to your medicines, and you may need to monitor your blood sugar level more often. Keep in regular contact with your dietitian or diabetes nurse, particularly when starting new treatments.

If you are well, have a good appetite and haven’t lost weight, you may be told to follow a healthy diet. Diabetes UK has information on following a healthy diet. If you have been on a particular diet for your diabetes, this may no longer be necessary, but talk to your medical team.

There are different types of diabetes, and information on the internet about changing your diet may not be right for you because of your pancreatic cancer. If you have lost weight or are struggling to eat, you may need more calories in your diet to help you put weight back on. This may include eating foods that increase your blood sugar level. Your diabetes will need to be managed around this.

Diabetes and pancreatic enzyme replacement therapy

Problems with digesting food should be managed with pancreatic enzymes. When you first start taking pancreatic enzymes, your blood sugar level may start to rise because you will start to digest your food properly again. This can change how your diabetes needs to be managed, and you may need more diabetes medicine.

If you forget to take pancreatic enzymes with food, your blood sugar level may drop. If this happens remember to take your enzymes with your next snack or meal.

What else can affect my blood sugar level?

If you are taking steroids, these can cause your blood sugar level to rise. Your doctor or nurse will need to monitor this, and they might change your diabetes medicine.

Infections can raise your blood sugar level. If you take insulin for your diabetes and have an infection, you will need advice on how to control your diabetes. If you take tablets for your diabetes, the tablets may not work properly if you are sick or have diarrhoea.

Some nutritional supplements are high in sugar, and your diabetes medicine may need to be changed.

Exercising can lower your blood sugar level, as your body uses the sugar as energy. You may need to eat more when you are exercising – even if you are only doing gentle activity. If you take insulin for your diabetes, you may need to monitor your blood sugar levels when exercising.

Questions about diabetes?

Managing diabetes if you have pancreatic cancer can be difficult and confusing. If you have any questions, speak to your dietitian, specialist cancer nurse, doctor or diabetes nurse. You can also speak to our specialist nurses on our free Support Line.

Speak to our nurses
Specialist nurse Nicci

Updated January 2020

Review date January 2023