Did You Know Certain Medications Can Impact Your Blood Sugars?
Most of us are familiar with factors that can affect blood glucose such as food, exercise, menstrual cycles, stress, etc., but have you ever considered how prescription medications can affect your blood glucose levels?
As a pharmacist living with type 1 diabetes, I know firsthand the effects that certain medications can have on blood glucose. It’s important to know that when you are prescribed a new medication, your provider may not always consider its potential effects on your blood glucose levels.
The intent of this article is to highlight the most common medications and medication classes that may cause hypo- or hyperglycemia, however, it is not all-inclusive. If you have a concern about a medication you are taking and how it might impact your diabetes, please speak to your healthcare provider.
How Can Medications Affect Blood Glucose?
Medications can cause blood glucose fluctuations by changing insulin secretion and sensitivity, glucose production by the liver, or by directly affecting beta cells.
Depending on the drug, hyper- or hypoglycemia can manifest within hours, weeks, or months after initiation.
The likelihood of experiencing blood glucose changes can also depend on medication dose or strength, medication frequency, duration of medication administration, and/or interactions with other medications. Additionally, within a specific drug class, the incidence of drugs causing blood glucose changes may also vary. Lastly, the route of drug administration in which the medication is given (i.e., by mouth, inhalation, etc.) and systemic availability of the drug, meaning the amount of the drug that actually reaches your body’s organs, can also influence a drug’s ability to cause hypo- or hyperglycemia.
Oftentimes after drug discontinuation, drug-induced hyperglycemia is reversible within days, but improvement in blood glucose levels may take longer with drugs like antipsychotics or corticosteroids that cause hyperglycemia by weight gain or insulin resistance.
Medications That Can Cause Hyperglycemia (High Blood Sugar)
Steroids
Oral steroids including prednisone, methylprednisolone, and dexamethasone are used to decrease inflammation in conditions such as asthma, COPD, rheumatoid arthritis, and inflammatory bowel disease. Steroids mimic the body’s cortisol, which stimulates the liver to release more glucose and reduce insulin effectiveness, causing elevated blood glucose levels. This is more common when steroids are taken orally (as pills) or by injection – it’s much less common with inhaled steroids.
Hyperglycemia is more likely to occur for people on high doses of steroids for a long period of time, but blood glucose levels typically return to normal when the steroids are discontinued or upon dose reduction.
Diuretics
Diuretics are used to reduce fluid buildup in the body and can also lower blood pressure. Thiazide and thiazide-like diuretics like hydrochlorothiazide (aka HCTZ), chlorthalidone, and metolazone can decrease potassium levels in the body, which decreases insulin secretion and sensitivity. These effects depend on the dose of the diuretic, however, taking a prescription potassium supplement can help offset this effect.
Beta-Blockers
These medications are used to treat irregular heart rhythm, chronic chest pain, and heart failure. Atenolol, metoprolol, and propranolol are beta blockers that can lower insulin sensitivity and/or insulin secretion. Other beta blockers like nebivolol and labetalol have not been found to affect blood glucose levels.
Statins
Statins are cholesterol-lowering medications that can increase insulin resistance and decrease insulin secretion. They may cause small elevations in glucose levels, but it’s typically not a clinically relevant difference. The more potent lipid-lowering statins like atorvastatin, rosuvastatin, and simvastatin are more likely to increase blood glucose than the less potent statins like pravastatin.
Statins can help decrease the risk of heart attack and stroke, so the benefit of taking a statin greatly outweighs any potential hyperglycemia. However, if the hyperglycemia is consistent, your provider can lower your statin dose or increase the dose(s) of your diabetes medication(s).
Antipsychotics
Second-generation antipsychotics (SGAs) are used to treat mental health disorders. This drug class can cause metabolic syndrome, including weight gain and/or decreased insulin sensitivity and secretion. Clozapine, olanzapine, and paliperidone are more commonly linked to these effects than other SGAs like aripiprazole, lurasidone, or ziprasidone.
Immunosuppressants
Organ transplant medications like tacrolimus, sirolimus, everolimus, and cyclosporine can decrease insulin sensitivity and secretion, which can be intensified by taking a steroid since they are often prescribed together. Providers can adjust diabetes medications to compensate for these effects.
Medications That Can Cause Hypoglycemia (Low Blood Sugar)
Glucose Lowering Drugs
This may seem obvious, but taking a variety of diabetes medications can increase hypoglycemia risk. Medication classes most commonly linked to hypoglycemia are insulin and sulfonylureas (glipizide and glimepiride), which increase insulin secretion. Other diabetes medication classes are infrequently linked to hypoglycemia.
SGLT-2 inhibitors such as Farxiga, Jardiance, and Invokana increase glucose excretion in the kidneys, which lowers blood glucose levels and decreases insulin secretion from the pancreas. A rare complication of SGLT-2 inhibitors is called euglycemic diabetic ketoacidosis, which means that DKA can occur even with normal blood glucose levels. DKA symptoms include severe nausea, vomiting, fatigue, abdominal pain and/or a fruity odor regardless of blood glucose levels. If you are taking an SGLT-2 inhibitor, it’s important to monitor for these symptoms and immediately report them to your provider if they occur.
Beta Blockers
Propranolol, labetalol, and carvedilol do not cause hypoglycemia, but they can mask symptoms like rapid heart rate and shakiness, which can cause hypoglycemia unawareness in people who take insulin. Beta blockers, however, don’t mask sweating symptoms.
Angiotensin-Converting Enzyme (ACE) Inhibitors
Medications like lisinopril, ramipril, and enalapril are used to treat high blood pressure and protect the kidneys in people with diabetes, but they can also cause hypoglycemia by increasing insulin sensitivity. This seems to be more common in the first few weeks after starting an ACE-Inhibitor and people with kidney disease may be at a higher risk.
Effective Management Strategies
If you are prescribed a medication that is known to cause hyper- or hypoglycemia, discuss the benefits versus the risks of taking the medication with your pharmacist. Usually these adverse effects can be managed with more frequent blood glucose monitoring or adjustments to your diabetes medication doses.
It’s important to ensure your provider has a complete list of your medications, including over-the-counter (OTC) medications and supplements, so he or she can best determine impacts on blood glucose. Remember to never discontinue a medication without first speaking with your provider.
If you want to learn about over-the-counter medicines that can affect blood glucose, please read 10 Tips to Use Over-the-Counter Medications Safely with Diabetes.
Additional Resources:
What to Ask Your Pharmacist When Starting a New Medication
10 Tips to Use Over-the-Counter Medications Safely with Diabetes
How to Keep DKA at Bay: Signs, Symptoms, and Solutions
Medicines for children, such as Amoxicillian, the pink liquid kind, to be taken orally, have sugar in them to make them more readily taken by children.
So, if the child has an ear infection and is Type 1, that additional sugar needs to be considered.
You’re absolutely right, and don’t forget that blood sugars will go up with any type of infection as well, so keep an eye on the CGM and give correction doses as needed.
What about the effect of edible cannabis taken for gastroparesis? I.e.tincture or lozenges taken before lunch & dinner. Just add in carb count to pump bolus?
Yes, that’s always a good idea, but you might want to experiment by not taking any bolus when you’re in a steady state, as you may not need to bolus. You don’t want to get low when you’re high!
The statin effect (particularly with high-potency statins) is real. To the point that if I’m more resistant or sensitive on a particular day, one of the first things I do is think back and consider if I either forgot to take the statin, or spaced out and double-dosed it accidentally.
Skipping a statin or taking a double dose here or there has no negative effects.
And don’t forget acetaminophen giving false hyper readings with some CGMs…
Not anymore. That was the old G5.