Prednisone is a steroid that works in a similar way to cortisol, which the adrenal glands usually produce in response to stress. Steroids can affect how the body reacts to insulin, a hormone that controls the level of sugar in the blood.
As a result, people who are at risk of diabetes or have this condition already need to apply caution before taking steroids.
People use steroids to treat a wide range of conditions, including autoimmune disorders and problems relating to inflammation, such as arthritis. They work by reducing immune activity and inflammation, so they can help prevent tissue damage.
In this article, we explain the connection between prednisone and diabetes and provide practical steps that a person can take to manage the risks.
Prednisone and other steroids can cause a spike in blood sugar levels by making the liver resistant to insulin. The pancreas produces insulin to control blood sugar levels.
Diabetes can result from a fault in the way that the body reacts to insulin or a problem with the production of insulin in the pancreas.
When blood sugar levels are high, the pancreas secretes insulin, and it travels to the liver.
The arrival of insulin at the liver triggers a drop in the amount of sugar that this organ typically releases to fuel the cells. Instead, sugar enters the cells straight from the bloodstream. This process reduces overall blood sugar concentration.
Steroids can make the liver less sensitive to insulin because they cause it to carry on releasing sugar, even if the pancreas is also releasing insulin. This continued release of sugar triggers the pancreas to stop producing the hormone.
If this process continues, it causes insulin resistance. The cells no longer respond to insulin, regardless of whether the body produces it or a person injects it to control diabetes.
Doctors refer to this condition as steroid-induced diabetes.
Steroid-induced diabetes is similar to type 2 diabetes in that the cells fail to react appropriately to insulin.
Diabetes is a condition that causes blood sugar levels to become consistently too high. Two main types of diabetes usually develop:
- type 1 diabetes, in which the pancreas fails to produce any insulin
- type 2 diabetes, in which the pancreas fails to produce enough insulin or the cells do not react to the insulin circulating the body
Steroid-induced diabetes should resolve soon after the conclusion of steroid treatment. Type 1 and type 2 diabetes, on the other hand, are lifelong conditions that require ongoing management.
The symptoms of steroid-induced diabetes are the same as those of type 1, type 2, and gestational diabetes, which affects some women during pregnancy.
- dry mouth
- feeling tired
- unintentional weight loss
- frequent urination
- blurred vision
- nausea and vomiting
- dry, itchy skin
- tingling or loss of feeling in the hands or feet
Some people can experience high blood sugar levels without showing any symptoms. For this reason, people should regularly monitor their blood sugar levels after starting a course of steroids.
As with other types of diabetes, a person with steroid-induced diabetes should make lifestyle adjustments to improve their blood sugar control.
These changes might include eating a healthful, balanced diet and partaking in regular exercise.
When steroids trigger diabetes, blood sugar will usually spike within 1–2 days of starting the course of treatment. If a person takes steroids in the morning, blood sugar will usually rise by the afternoon or evening.
People taking steroids should regularly monitor their blood sugar levels and may need to take oral medication or insulin if these levels become too high.
Generally, blood sugar levels should return to their previous levels 1–2 days after finishing steroid treatment. However, some people may develop type 2 diabetes as a result and will need appropriate follow-up treatment with oral medication or insulin therapy.
The risk of developing steroid-induced type 2 diabetes is highest in people who are taking large doses of steroids over extended periods.
Other risk factors for type 2 diabetes include:
- being aged 45 years or older
- being overweight
- a family history of type 2 diabetes
- a personal history of gestational diabetes
- impaired glucose tolerance
For people with certain conditions, taking prednisone and other steroids will be unavoidable. These medicines can give a person the best chance of recovery or pain relief, even if they also have diabetes.
People with diabetes will need to take the following steps before starting a course of prednisone or a similar medication:
Make the doctor aware of their diabetes diagnosis. The doctor may sometimes be able to prescribe a different drug that does not interfere with blood sugar levels.
If this is not possible, they will often need to make adjustments to the prescribed dosage to keep blood sugar levels within the target range.
- Check blood glucose levels more often than usual. Experts recommend doing this four or more times a day.
- Increase the dosage of insulin or oral medication, depending on blood sugar levels and whether a doctor advises it.
- Monitor urine or blood ketones.
- See a doctor immediately if blood sugar levels rise too high while taking steroids, and the insulin or oral medication dose is not high enough to bring the levels down.
- Carry glucose tablets, juice, or candy at all times in case blood sugar levels drop suddenly.
As a person gradually reduces their dosage of steroids, they should also reduce the equivalent dosage of insulin or oral medication until it returns to the original dosage. It is important never to stop taking steroids suddenly as this may cause severe illness.
People with diabetes often need to take medications for other conditions. Any medication can increase the risk of the person experiencing harmful drug interactions if they are also taking insulin.
The most common oral drugs that people take for diabetes are called oral hypoglycemics.
These medications include:
- biguanides, such as metformin (Glucophage)
- alpha-glucosidase inhibitors, such as acarbose (Glucobay, Precose)
- sulfonylureas, such as glyburide (Micronase, DiaBeta)
- meglitinides, such as repaglinide (Prandin)
- thiazolidinediones, such as rosiglitazone (Avandia)
All of these drugs have the potential to interact with other medications. People should take extra caution with sulfonylureas, metformin, and thiazolidinediones, particularly when they are taking them to treat any of the following conditions:
- liver dysfunction
- cardiovascular disease
- kidney disease
Doctors might include insulin therapy in a treatment plan for steroid-induced diabetes if an individual does not respond to lifestyle changes or oral medications.
Many medications interact with insulin, including:
- ACE inhibitors
- hypothyroid drugs
- monoamine oxidase inhibitors (MAOIs)
- oral contraceptives
- sulfa antibiotics
People who have diabetes should always discuss possible drug interactions with their doctor.
I switched from taking prednisone, and my blood sugar levels are still dangerously high. What can I do next?
Continue to monitor your blood sugar at least four times a day, exercise regularly, eat healthful, balanced meals, and carry on taking medications or insulin according to your prescription.
If your blood sugar remains high for more than 2 or 3 days after stopping steroid therapy, contact your doctor.Alan Carter, PharmD Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.