Corticosteroids and Diabetes: How Steroids Cause High Blood Sugar and How to Manage It
Stuart Moore 14 November 2025 9

Steroid-Induced Diabetes Insulin Calculator

Steroid Dosage & Current Insulin

Typical dose: 5-60 mg/day
Recommended if you take >20 mg prednisone daily
Total daily carbs: 150-300g for most adults
Important Safety Note: Never stop steroids without medical supervision. If blood sugar exceeds 250 mg/dL or drops below 70 mg/dL, contact your doctor immediately.

When you take corticosteroids like prednisone or dexamethasone for asthma, arthritis, or an autoimmune flare-up, you’re not just fighting inflammation-you might be setting off a hidden metabolic bomb. Up to 50% of people on high-dose steroids develop high blood sugar, even if they’ve never had diabetes before. This isn’t just a side effect. It’s a full-blown metabolic disruption that can land you in the hospital if ignored.

Why Corticosteroids Spike Your Blood Sugar

Corticosteroids don’t just make your immune system quieter-they mess with how your body handles sugar at every level. It’s not one problem. It’s four working together.

First, your liver starts pumping out way more glucose. Glucocorticoids turn on enzymes that turn fat and protein into sugar, even when you’re not eating. Studies show this boosts glucose production by 35-40%. Your body thinks it’s in a stress state and needs fuel-fast.

Second, your muscles stop listening to insulin. Normally, insulin tells muscle cells to grab glucose from your blood. Steroids block that signal. GLUT4 transporters, the doorways that let glucose in, get shut down. Result? Your muscles absorb 30% less sugar than they should. That glucose stays in your bloodstream.

Third, your fat cells go into overdrive. Steroids break down fat faster, flooding your blood with free fatty acids. These acids interfere with insulin signaling even more, making insulin resistance worse. It’s a loop: more fat breakdown → more fatty acids → more insulin resistance → higher blood sugar.

Fourth, your pancreas starts to fail. Beta cells, which make insulin, get confused. Steroids reduce the number of glucose sensors (GLUT2 and glucokinase) on these cells. They also mess with the internal signals that trigger insulin release. In some cases, insulin production drops by 20-35%. So you’re not just resistant to insulin-you’re not making enough of it.

Who’s Most at Risk?

Not everyone on steroids gets high blood sugar. But some people are walking into a storm with no umbrella.

If you’re taking 7.5 mg or more of prednisone daily, your risk jumps 3.2 times. Dexamethasone? Even worse-just 0.75 mg daily triples your risk. Higher doses = higher danger.

Age matters. If you’re over 50, your risk is 3.1 times higher. Being overweight? That’s a 2.5-fold increase. Family history of diabetes? 2.7 times more likely. If you had gestational diabetes before? Your risk skyrockets to 4.3 times. And if your kidneys aren’t working well (eGFR under 60), you’re nearly 4 times more likely to crash into hyperglycemia.

Even the timing counts. The longer you’re on steroids, the worse it gets. Each extra week beyond two weeks increases your risk by 12%. And if you’re on a high dose for more than a month, your chances of developing full-blown steroid-induced diabetes are over 30%.

What Does It Feel Like?

Some people feel it right away. Others don’t notice anything until their blood test comes back.

Common symptoms: extreme thirst (65% of cases), peeing all the time (72%), constant fatigue (81%), and headaches (43%). But here’s the trap: steroids also cause increased hunger, weight gain, blurred vision, and mood swings. So if you’re gaining 3-4 kg in a month and feeling hungrier than usual, is it the steroids-or is your blood sugar spiking?

That’s why 40% of cases are silent. No symptoms. Just rising numbers on a glucose meter. That’s why routine monitoring isn’t optional-it’s lifesaving.

Patient checking glucose monitor as skeleton doctor offers insulin, healthy food beside discarded sweets.

How Doctors Monitor and Diagnose It

If you’re on prednisone at 20 mg/day or more, or any equivalent high-dose steroid, your doctor should check your blood sugar at least twice a day. Fasting levels above 140 mg/dL (7.8 mmol/L) or random levels over 180 mg/dL (10.0 mmol/L) mean it’s time to act.

For people with existing type 2 diabetes, insulin needs often jump by 50-100% during steroid treatment. That’s not a mistake-it’s physics. Your body is fighting a war on two fronts: inflammation and sugar overload.

Timing matters too. Steroids like prednisone peak in your system 4 to 8 hours after you take them. That’s when your blood sugar hits its highest point. So if you take your steroid in the morning, check your glucose around lunchtime or early afternoon-not just before breakfast.

And here’s something most patients don’t know: once you stop the steroid, your blood sugar usually drops back to normal in 3 to 5 days. That’s why it’s called steroid-induced diabetes-not permanent diabetes. But if you’re not monitored, you might be stuck on diabetes meds you don’t need.

How to Treat It

Treatment isn’t one-size-fits-all. It depends on your dose, your risk, and whether you already have diabetes.

Basal insulin is the go-to for most people on high-dose steroids. It’s steady, long-lasting, and covers the liver’s sugar overproduction. The standard rule: increase basal insulin by 20% for every 10 mg above 20 mg of prednisone. So if you’re on 40 mg/day, you’ll likely need 40% more basal insulin than your usual dose.

Rapid-acting insulin handles meal spikes. A common starting ratio is 1 unit per 5-10 grams of carbs. But you might need to adjust this daily as your sugar levels change.

Sulfonylureas (like glipizide) can help by forcing your pancreas to release more insulin. But they’re risky. When your steroid dose is lowered or stopped, your insulin production doesn’t bounce back immediately. That means you can crash into low blood sugar-sometimes dangerously so. In fact, 37% of hypoglycemia events during steroid taper are linked to improper sulfonylurea use.

GLP-1 receptor agonists (like semaglutide) are showing promise in early trials. They help lower blood sugar without causing hypoglycemia and even reduce appetite-which helps with steroid-induced weight gain. The NIH’s GLUCO-STER trial is still ongoing, but early results show 28% fewer low blood sugar episodes compared to insulin.

Person walking from hospital to garden as sugar clouds become butterflies, symbolizing temporary steroid diabetes.

What You Can Do

You’re not powerless. Here’s what works:

  • Ask for a glucose monitor before you start steroids. Don’t wait for symptoms.
  • Check your blood sugar twice daily-fasting and 2-4 hours after your steroid dose.
  • Track your carb intake. Steroids make you crave sugar and carbs. Fight it with protein, fiber, and healthy fats.
  • Stay active. Even a 20-minute walk after meals helps your muscles use glucose without insulin.
  • Don’t assume it’s permanent. If you’re on steroids for 2 weeks, your diabetes might be too.
  • Ask for a follow-up glucose test 1 week after stopping steroids. If it’s normal, you may not need diabetes meds anymore.

What’s Changing in 2025

The tide is turning. In 2023, the European Association for the Study of Diabetes launched the STEROID-Glucose app. It links your steroid dose to your glucose readings and gives real-time insulin adjustment advice. In pilot studies, users saw a 32% drop in high blood sugar events.

Researchers are also testing new drugs called tissue-selective glucocorticoid receptor modulators. One compound, XG-201, reduces inflammation like prednisone-but causes 65% less hyperglycemia. Phase II trials are promising.

And it’s not just about arthritis or asthma anymore. Steroids are now used in 75-85% of patients getting CAR-T cell cancer therapy. That’s a whole new population at risk-and hospitals are scrambling to keep up.

By 2030, experts predict steroid-induced diabetes will become the third most common cause of secondary diabetes, behind only pancreatic disease and Cushing’s syndrome. That’s not a prediction-it’s a warning.

Final Thought

Corticosteroids save lives. But they don’t come without cost. High blood sugar isn’t a footnote-it’s a central part of the treatment plan. If your doctor doesn’t mention it, ask. If your glucose levels are rising, don’t wait. This isn’t just about numbers on a screen. It’s about avoiding diabetic ketoacidosis, kidney damage, nerve injury, and hospital stays that could have been prevented.

Take your steroid. But take control of your blood sugar too.

Can corticosteroids cause diabetes in people who never had it before?

Yes. Corticosteroids can trigger steroid-induced diabetes in people with no prior history. This happens in 10-30% of those on high-dose therapy. It’s caused by insulin resistance, increased liver sugar production, and reduced insulin secretion-not by the same mechanisms as type 1 or type 2 diabetes. Blood sugar usually returns to normal within days after stopping the steroid.

How long does it take for steroids to raise blood sugar?

Blood sugar can rise within 24 to 48 hours of starting high-dose steroids. The peak effect usually occurs 4 to 8 hours after taking the dose. For example, if you take prednisone in the morning, your blood sugar may spike by lunchtime. This timing matters for when you check your glucose and take insulin.

Is steroid-induced diabetes permanent?

No, it’s usually temporary. Once you stop taking corticosteroids, blood sugar levels typically return to normal within 3 to 5 days. However, if you already had prediabetes or insulin resistance before starting steroids, you may be more likely to develop long-term type 2 diabetes. Always get a follow-up glucose test after stopping treatment.

What’s the best medication for managing steroid-induced hyperglycemia?

Basal insulin is the most effective and safest choice for most patients. It counters the liver’s excess glucose production. Rapid-acting insulin helps with meals. Sulfonylureas can raise insulin levels but carry a high risk of low blood sugar when steroids are tapered. GLP-1 agonists are emerging as promising alternatives with fewer hypoglycemia risks.

Should I stop taking steroids if my blood sugar goes high?

Never stop steroids without talking to your doctor. Abruptly stopping can cause adrenal crisis, which is life-threatening. Instead, work with your provider to adjust your insulin or other diabetes medications while continuing the steroid. Your steroid dose may be reduced later, but only under medical supervision.

How often should I check my blood sugar on steroids?

If you’re on prednisone 20 mg/day or higher, check your blood sugar at least twice daily-once fasting and once 4 to 8 hours after your steroid dose. For lower doses or shorter courses, your doctor may recommend once-daily checks. If you have existing diabetes, you may need to check 3-4 times a day.

Can diet and exercise help with steroid-induced high blood sugar?

Yes. Reducing refined carbs and sugar helps, but it’s not enough on its own. Exercise-especially walking after meals-improves insulin sensitivity and helps muscles use glucose without insulin. Even 20 minutes of walking after your steroid dose can lower your blood sugar by 15-25 mg/dL. But you still need medication for most people on high-dose steroids.

What should I do if I feel dizzy, confused, or extremely tired on steroids?

Check your blood sugar immediately. These symptoms can mean either very high blood sugar (hyperglycemia) or dangerously low blood sugar (hypoglycemia), especially if you’re on insulin or sulfonylureas. If your sugar is over 250 mg/dL and you’re feeling unwell, contact your doctor. If it’s under 70 mg/dL, treat it with fast-acting sugar and call for help if you don’t improve in 15 minutes.