If you take metoprolol for high blood pressure, heart failure, angina, or another heart-related condition, you may already know that it can slow your heart rate and lower your blood pressure.
What you may not realize is that some effects can feel surprisingly ordinary.
You might simply feel more tired than usual. You may become lightheaded when standing up, notice colder hands and feet, sleep differently, or find that exercise feels harder than it used to.
These changes don’t necessarily mean something is wrong with your treatment. Metoprolol is prescribed because its benefits can be important. But persistent or bothersome symptoms are worth discussing with your healthcare professional rather than quietly putting up with them.
Metoprolol is a beta-blocker used for conditions including high blood pressure, angina, heart failure, and after certain heart attacks. It works partly by slowing the heart and reducing the workload on it.
Here are 10 effects that can be easy to overlook.
1. Persistent tiredness or low energy
Feeling unusually tired is one of the more commonly reported side effects of metoprolol.
Because fatigue is so common in everyday life, people may blame it on getting older, poor sleep, stress, or simply having a busy week.
But if you noticed a clear change after starting metoprolol or after your dose was increased, it is worth mentioning.
Clinical information for metoprolol lists tiredness among common adverse reactions, and MedlinePlus also advises patients to tell their doctor if tiredness is severe or does not go away.
Don’t stop the medication on your own. Your healthcare professional can determine whether the symptom is related to the medicine or something else.
2. Dizziness or lightheadedness when standing
Metoprolol lowers blood pressure and slows the heart rate. For some people, that can contribute to dizziness or lightheadedness, particularly when getting up quickly.
You might notice it when rising from a chair or getting out of bed.
Mayo Clinic specifically notes that dizziness, lightheadedness, and fainting can occur when standing suddenly, and recommends getting up slowly to help reduce the problem.
For an older adult, this symptom deserves particular attention because dizziness can increase the risk of losing balance or falling.
If you repeatedly feel as though you might faint, tell your healthcare professional rather than simply trying to tolerate it.
3. A slower heartbeat
One of the intended effects of metoprolol is to slow the heart rate.
That is part of how the medication works.
But if your heartbeat becomes unusually slow or you develop symptoms such as weakness, dizziness, fainting, chest discomfort, or unusual shortness of breath, your healthcare professional should know.
Metoprolol labeling includes bradycardia, meaning an abnormally slow heart rate, among its possible adverse effects.
Don’t judge the significance of a heart-rate number by itself. Your doctor can determine whether your rate is appropriate for your condition, dose, and overall health.
4. Feeling like exercise suddenly takes more effort
You may notice that walking uphill, climbing stairs, gardening, or exercising feels harder than it used to.
This can make sense because metoprolol reduces heart rate and changes the heart’s response to physical activity.
That does not necessarily mean you should stop exercising.
Instead, tell your healthcare professional if your exercise tolerance has changed substantially or unexpectedly. Mayo Clinic lists decreased exercise ability among potential effects associated with metoprolol-related treatment considerations.
There can also be other explanations for a sudden reduction in exercise tolerance, including anemia, lung problems, heart disease, poor sleep, or deconditioning.
The change itself is what deserves attention.
5. Sleep problems or unusually vivid dreams
Sleep changes are another effect that can be easy to overlook.
Mayo Clinic lists trouble sleeping and nightmares among possible less-common effects of oral metoprolol.
Someone may not immediately connect a new sleep problem with a medication, particularly if the change develops gradually.
If you started having noticeably worse sleep, frequent nightmares, or another unusual change after beginning or changing metoprolol, keep track of when it happens and discuss it with your healthcare professional.
Do not change the timing or dose yourself unless your prescriber recommends it.
6. Mood changes or feeling unusually down
Metoprolol has been associated with depression and other mood-related symptoms in some patients.
The prescribing information for metoprolol tartrate lists depression among reported adverse reactions, while Mayo Clinic also lists feelings such as sadness or loss of interest among possible less-common effects.
That doesn’t mean metoprolol is necessarily responsible whenever someone’s mood changes.
Life circumstances, illness, sleep, other medications, and many other factors can affect mood.
But if you notice a persistent change that began after starting the medication, mention it to your doctor.
And if you experience thoughts of harming yourself or feel that you are in immediate danger, seek urgent help rather than waiting for a routine appointment.
7. Sexual side effects
This is a topic people sometimes hesitate to bring up.
Metoprolol can be associated with sexual side effects, including decreased sexual interest and difficulty achieving or maintaining an erection. Mayo Clinic lists these effects among possible adverse reactions.
Because people may feel embarrassed discussing sexual health, the connection with a medication can go unmentioned.
There is no need to be embarrassed. Your healthcare professional hears these concerns regularly and can determine whether metoprolol, another medication, an underlying condition, or another factor could be contributing.
Don’t stop a heart or blood-pressure medication because of this without discussing alternatives with your prescriber.
