Diabetes and steroids

Steroids can increase your blood sugar levels if you have diabetes. This treatment can also cause high blood sugar in people who do not have diabetes.

About steroids

Steroids (also called corticosteroids) are naturally produced in the body. They help control the way the body works, including how it uses food. Steroids are also drugs often used for cancer treatment. They can be given as tablets, injections or as a drip (infusion).

Steroids drugs can be used:

  • as part of your treatment, to help destroy some types of cancer cell and make chemotherapy work better
  • to help reduce an allergic reaction to certain chemotherapy drugs
  • in small amounts as anti-sickness drugs
  • to treat the side effects of some cancer drugs, such as immunotherapy drugs
  • to improve your appetite.

How steroids can affect your diabetes

Steroids can increase blood sugar levels in people with or without diabetes. This is called steroid-induced hyperglycaemia.

While you are taking steroids, it might be more difficult to manage your blood sugar levels. This will depend on the type of diabetes you have and how you normally manage your diabetes. It also depends on the following:

  • which steroids you are taking
  • the dose – the higher the dose, the more likely your blood sugars will increase
  • the time of day you take them
  • how the steroids are given – your blood sugars may rise faster with a steroid infusion (drip) or injection than with tablets
  • how long you take steroids for.

Managing your blood sugar level when taking steroids

Before you start taking steroids, talk to your doctors about how to keep your blood sugar level within your target range.

Checking your blood sugar level

It is very important that your blood sugar level is checked regularly during steroid treatment. You will have your blood sugar tested when you go to the hospital.

If you do not already check your blood sugar level at home, you will need to start checking it. Make sure you have blood-testing equipment at home. If you already check your blood sugar level, you may need to check it more often.

Keep a record of your blood sugar level. This will help you see if there is a pattern.

If your blood sugar is high

Talk to your cancer doctor, diabetes team or GP as soon as possible if any of the following happen:

Your blood sugar level is high (12mmol/l or more) on more than 2 or 3 occasions.

It is important to regularly contact your diabetes team during cancer treatment. This is because your diabetes management may need to change regularly during your treatment.
If your blood sugar level stays high while you are taking steroids, your cancer doctor or specialist nurse may change the dose of the steroids and the time you take them. 

Changing your diabetes treatment

You may also need to change the way you manage your diabetes. Your diabetes team will advise you how to do this. For example:

  • if you use your diet to manage your blood sugars, you may need to start taking tablets
  • if you take tablets, you may need to increase the dose or start using insulin for a short time
  • if you use insulin, you may need to increase the dose or use a different type of insulin.

Correction doses of insulin can be used to reduce very high blood sugars. These may not work as well when you are taking steroids. Contact your diabetes team first for advice. They may suggest you take more insulin.

Stopping steroids

Never stop taking your steroids without talking to your cancer doctor first.

The dose of steroids you take as part of your cancer treatment will usually be reduced and stopped.

Date reviewed

Reviewed: 01 September 2023
Next review: 01 September 2026
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

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