Beta-blockers can cause either low blood sugar (hypoglycemia) or high blood sugar (hyperglycemia). They can also mask the symptoms of low blood sugar, meaning that a person may not be aware they have it.
It is not clear why beta-blockers can cause hypoglycemia. However, a
Nadolol had the strongest association with hypoglycemia. The authors say this may be because it has a longer half-life than other drugs and is nonselective, which means it can bind to
In the study, hypoglycemia was also more likely to occur in children who were taking these drugs, but this reaction could potentially occur in anyone.
Beta-blockers can also lead to high blood sugar in some people. Scientists do not fully understand why, but a 2024 review notes that the drugs may affect glucose metabolism.
Past research cited in the review suggests that beta-blockers decrease insulin secretion while increasing insulin resistance and glucose production. These effects can raise blood sugar levels.
Previous studies have suggested that beta-blockers may raise the risk of hyperglycemia by 20% to 25%. However, the effects can be reversible if a person stops taking the medication.
These potential complications may mean that beta-blockers are not suitable for some people, such as those with diabetes.
People who have concerns about their blood sugar should talk with their doctor about the potential risks and benefits. A person should not stop taking beta-blockers or change their dose without first consulting a doctor.
If a person is at risk of low or high blood sugar or has symptoms of either, a doctor may be able to suggest alternative drugs or other strategies to minimize the risk.
