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Metoprolol and Low Blood Sugar
Blood sugar levels may be affected by metoprolol, and low blood sugar is more likely to occur in infants or children and people who have kidney disease or diabetes. Early symptoms that may indicate low blood sugar levels include dizziness, sweating, and extreme hunger. Since low blood sugar levels can cause serious or life-threatening complications, it is important to know the possible signs and what to do if they occur.
Metoprolol (Lopressor®, Toprol XL®) belongs to a group of medications known as beta blockers. Low blood sugar levels have been reported in people taking such drugs. Normal doses of metoprolol probably do not significantly increase the risk of low blood sugar for most people. However, Toprol-XL can make low blood sugar less noticeable (which can be dangerous, especially for people with diabetes).
This potential side effect of beta blockers is more common in infants and children, while fasting (such as before surgery), after prolonged exercise, or in people with kidney disease or diabetes.
Low blood sugar symptoms can vary, depending on a number of factors, including how low the blood sugar levels are. Examples of early symptoms may include:
- Sweating
- Shakiness
- Extreme hunger
- Dizziness
- Cold sweats
- Blurry vision.
More severe symptoms of low blood sugar can include:
- Changes in behavior, such as irritability
- Loss of coordination
- Difficulty speaking
- Confusion
- Seizures
- Loss of consciousness
- Coma
- Loss of life.
Two other symptoms that can occur in people with low blood sugar are an increase in heart rate and blood pressure. In people taking metoprolol, these low blood sugar symptoms may not occur because of the effects of the medicine. Therefore, metoprolol can "mask" these important symptoms, perhaps making low blood sugar less noticeable (and therefore more dangerous).
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD



