5 medications that can affect blood sugar

If you have diabetes, you know that you have to monitor your food (specifically sugar) intake and blood sugar (glucose) levels—and you might also have diabetes medications that you take that you have to factor in. However, did you realize that other medications—including prescription and over-the-counter (OTC) meds—can also affect your blood glucose levels?

If you haven’t thought of that, you’re not alone. Often, if people see that their blood sugar levels have changed, they fix their diet or insulin, says Jasmine Gonzalvo, PharmD, BCPS, BC-ADM, C.D.E., L.D.E., a clinical associate professor at Purdue University and spokesperson for the American Association of Diabetes Educators. In reality, it could be a medication they're taking that's throwing things off.

If your blood sugar levels seem unusually high or low, it's best to discuss all the medications you're taking with a certified diabetes educator (C.D.E.) or your doctor, says Gonzalvo. This includes prescriptions, vitamins, and mineral or herbal supplements. “They can help you think through the risks and benefits of using the medicine,” she says.

But in the case of certain heart and cholesterol prescriptions, the benefits of taking a medication can outweigh the risks of changing blood sugar, says Gonzalvo. “There are other options to make sure your blood sugar stays healthy—like physical activity and healthy diet choices—that you can discuss with a diabetes educator,” she says. “There’s often not enough focus on the lifestyle part of the picture.”

Here are five common medications and supplements that can affect blood glucose.

1. Medications for Certain Conditions

Several types of medication can raise blood sugar, including cholesterol-lowering medicines (including niacin and statins); allergy, asthma, and inflammation medicines (specifically steroids, like those in some nasal sprays); and antipsychotic medicines (used to treat schizophrenia).

2. Beta-blockers

These high blood pressure medications can mask the signs of low blood sugar, such as a rapid heartbeat. Ask your C.D.E., pharmacist, or doctor if you should take special precautions when on these medications. Also be sure to check your blood sugar often when you start a beta-blocker.

3. Antibiotics

Certain antibiotics can impact blood sugar—and so can fighting an illness or infection. “If you’re sick, continue to take your diabetes medication, including insulin, and check your blood sugar frequently,” says Gonzalvo.

4. Cough Medicine

Cough medicine and other syrups (such as liquid pain relievers) often contain sugar. Ask your pharmacist if there’s a sugar-free formula. Many syrups also contain alcohol, although there’s typically not enough alcohol to have much of an effect on blood sugar. Still, you’re smart to limit your intake of alcoholic beverages, as they can cause a dangerous drop in your blood sugar levels.

5. Cinnamon Supplements

When taken as a supplement, this kitchen spice can lower blood sugar—but only a modest degree. Unless you’re using several tablespoons in a serving of food, cinnamon is not likely to cause a problem if you’re using it for cooking or baking.