The 10 Most Common Toprol XL (Metoprolol Succinate) Side Effects

High blood pressure and heart disease are among the most common health conditions worldwide. Because of this, drug makers have made it a priority to develop medications that help keep these conditions under control.

Toprol XL (metoprolol succinate) is one popular example. It falls into a class of medications called beta blockers. It’s slightly different from its sibling Lopressor (metoprolol tartrate), but they both slow down your heart rate, lower your blood pressure, and treat chest pain (angina). It can also lower the risk of hospitalization and death among those with heart failure.

Overall, metoprolol succinate is a well-tolerated and effective medication. But it still has some potential risks to keep in mind. Below, we’ll talk about 10 Toprol XL side effects to be aware of.

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1. Fatigue

Toprol XL can cause fatigue. This side effect was seen in up to 5% of people receiving the medication in early studies, with a higher risk among those receiving higher doses. It’s believed that fatigue is caused by the medication’s ability to pass into the brain and contribute to temporary brain-related side effects.

Fatigue doesn’t usually cause long-term issues, but it can be problematic in certain cases. That’s why it’s recommended that you avoid driving or participating in other tasks that require you to be alert until you know how the medication affects you.

Some lifestyle modifications can also help manage daytime fatigue:

• Improve your sleep hygiene when possible, such as prioritizing sleeping in a dark, quiet environment and avoiding caffeine in the evening.

• Exercise regularly and eat a nutritious diet to help boost your energy levels.

• Speak to your healthcare provider about what time of day to take the medication (such as taking doses at night rather than in the morning).

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2. Dizziness

One of Toprol XL’s primary goals is to lower your blood pressure to a normal range. However, lowering blood pressure can result in less blood flow and oxygen to the brain — causing dizziness. In severe cases, this may even lead to fainting. 

Thankfully, this side effect is usually short lived. It tends to happen soon after starting Toprol XL and after dose increases.

If you feel lightheaded or that your surrounding environment is in motion, try to take it easy. You may want to sit down or move slowly to avoid the risk of falling down.

If dizziness doesn’t go away with time, it’s a good idea to talk to your healthcare provider about how to get your symptoms under control.

3. Low blood pressure

Even though Toprol XL treats high blood pressure, it can sometimes lower it a bit too much. This is more common when you’re first starting Toprol XL and should get better over time.

Low blood pressure doesn’t always cause noticeable symptoms. So it's a good idea to routinely monitor your blood pressure at home to make sure it stays within your target range. But it’s important to be aware of possible symptoms of really low blood pressure, too, such as:

• Blurred vision

• Dizziness

• Lightheadedness

• Weakness

You should notify your healthcare provider if you notice these symptoms frequently. They may want to adjust your dose or change your medication regimen. Low blood pressure is more likely to happen if you also take other medications that lower your blood pressure.

4. Itching and rash

Itchiness and skin rashes are also relatively common side effects among people taking Toprol XL. These skin symptoms are often mild and manageable. But they can occasionally turn more serious and be related to an allergic reaction.

As a precaution, you should inform your healthcare provider right away if you develop a sudden rash. They can evaluate the severity of your symptoms and decide next steps.

5. Mood changes

Depression and anxiety are potential mood-related side effects of Toprol XL. However, depression and anxiety are also relatively common among people diagnosed with heart conditions. How long these symptoms last vary by person.

If you’re experiencing mood changes that are bothersome, don’t go away, or worsen at any point, make sure to contact your provider. Since everyone’s experience with depression is different, they can recommend personalized advice to support your mental well-being.

Although medications are available to improve depression, it’s not always necessary to take an antidepressant. These are some natural ways you can fight depression:

• Routinely exercising

• Eating a healthy diet

• Journaling

• Spending time in nature

• Getting social support

• Volunteering

Your healthcare provider can help you weigh your options and help you decide if an antidepressant, therapy, or another option is appropriate for your symptoms.

For additional resources or to connect with mental health services in your area, call SAMHSA’s National Helpline at 1-800-662-4357. For immediate assistance, call the National Suicide Prevention Lifeline at 988, or text HOME to 741-741 to reach the Crisis Text Line.

6. Diarrhea

Another relatively common side effect of Toprol XL is diarrhea. The reason why this happens isn’t fully understood. But it generally improves as your body adjusts to the medication.

When needed, some over-the-counter medication options can temporarily treat diarrhea, such as Imodium A-D (loperamide) and Pepto-Bismol (bismuth subsalicylate). Ask your healthcare provider or pharmacist if these are OK for you to take.

7. Low blood glucose concerns

Although rare, low blood glucose (sugar) is possible while taking Toprol XL. If you have diabetes, you’re probably aware of the symptoms that come along with this. Some common ones include shakiness, a fast heartbeat, and anxiety.

However, these symptoms may be harder to notice while taking Toprol XL. The medication may mask many symptoms of low blood glucose. But sweating is an exception. If you notice yourself feeling sweaty or clammy in an unusual situation, you may want to check your blood sugar.

Since relying on symptoms may not work, it’s a good idea to routinely monitor your blood glucose levels to make sure they stay within range.

8. Shortness of breath

Some people may experience shortness of breath while taking Toprol XL. This is mostly a concern if you have a history of asthma or chronic obstructive pulmonary disease (COPD). Taking a beta blocker with uncontrolled breathing problems is generally not recommended — it can worsen your lung function.

However, Toprol XL is less likely to cause breathing problems compared to many other beta blockers. It’s considered “cardioselective” because it primarily affects your heart. Nonselective beta blockers, like propranolol and carvedilol (Coreg), can affect your heart and your lungs. This can lead to worsened breathing.

9. Slow heart rate

Alongside lowering your blood pressure, Toprol XL can slow down your heart rate. And in some cases, it can slow it down too much.

A slow heart rate doesn’t always have symptoms. But it might in more serious cases. More serious symptoms of slow heart rate include:

• Dizziness or faintness

• Chest pain

• Sensation of skipped heartbeats

• Decreased exercise tolerance

If symptoms like these become frequent or bothersome, let your healthcare provider know as soon as possible. They may want to reduce your dose or switch you to a different medication altogether. In some cases, they may want to run tests to evaluate your heart health.

10. Worsening heart problems

Although very rare, Toprol XL has occasionally been linked to worsening heart failure. This can happen with both short- and long-term use, but it’s more likely to happen if you have pre-existing issues with your heart’s rate or rhythm. It may also occur while your provider is increasing your dose.

Toprol XL has also been linked to new or worsening heart block. This is when the medication interferes with your heart’s electrical activity and its ability to beat normally.

Because of risks like these, your healthcare provider likely won’t prescribe Toprol XL if you have decompensated heart failure, a condition called sick sinus syndrome, or certain types of heart block.

Keep in mind: This side effect is rare. Toprol XL is a first-choice option for managing certain types of heart failure.

What happens if I suddenly stop taking Toprol XL?

Toprol XL is a maintenance medication that’s designed to work over time. It’s not recommended to suddenly stop taking Toprol XL unless your healthcare provider specifically tells you to do so. If you stop taking Toprol XL suddenly, you’re more likely to experience chest pain. In some cases, heart attacks have also been reported.

Instead, this medication’s dose should be slowly reduced over 1 to 2 weeks. Your provider may want to monitor your heart rate and blood pressure during this time as a precaution, too.

When should I contact my healthcare provider about Toprol XL side effects?

Generally, Toprol XL is a well-tolerated medication. Certain side effects, such as fatigue and dizziness, are often mild and can be managed at home. Some side effects may not even be related to Toprol XL — they could be connected to an underlying health condition. 

However, you should contact your provider immediately for certain side effects, such as:

• Uncontrollable diarrhea

• Unexplained mood changes

• Abnormal itching or rash

• Slow heart rate

Other situations are more severe. They may require a trip to the nearest emergency room:

• Sudden chest pain

• Shortness of breath

• Really low blood pressure

• Really low blood glucose

How to save on Toprol XL

There are ways to save on Toprol XL, which is available as a generic- and brand-name medication. Anyone with a valid prescription, regardless of insurance status, can use GoodRx to purchase a 30-day supply of Toprol XL at an exclusive cash price as low as $39. You can also save by purchasing generic metoprolol succinate.

Why trust our experts?

Written by:

Yehun Lee, PharmD Candidate

During her doctoral program, Yehun has worked for Tops Pharmacy for 4 years as a pharmacist intern. There, she has been able to collaborate with other healthcare providers and patients alike.

Edited by:

Joshua Murdock, PharmD, BCBBS

Joshua Murdock, PharmD, BCBBS, is a licensed pharmacist in Arizona, Colorado, and Rhode Island. He has worked in the pharmacy industry for more than 10 years and currently serves as a pharmacy editor for GoodRx.

Reviewed by:

Christina Aungst, PharmD

Christina Aungst, PharmD, is a pharmacy editor for GoodRx. She began writing for GoodRx Health in 2019, transitioning from freelance writer to editor in 2021.

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