Lopressor (Metoprolol) Dosage and Side Effects
Lopressor is prescribed to treat high blood pressure and prevent angina (chest pain). It works by relaxing blood vessels and slowing heart rate, which improves blood flow and lowers blood pressure.
Warnings and Precautions
LOPRESSOR controls high blood pressure and chest pain, but it’s not a cure for these conditions.
It may also take a few weeks before you experience the full benefits of the drug.
If you have certain allergies, your reactions may be worse while you are taking LOPRESSOR. You also might not respond to your usual dose of epinephrine.
People with asthma, a slow heart rate, or heart failure should not use beta blockers, including LOPRESSOR.
Doctors should prescribe this drug with caution for older people and those with diabetes.
Before taking LOPRESSOR, be sure to tell your doctor if you have a slow heart rate or problems with blood circulation.
Your doctor also needs to know if you have any of the following:
- Asthma or another lung condition
- Liver disease
- Hyperthyroidism (an overactive thyroid)
- Congestive heart failure
- Certain types of irregular heartbeats
You should also let your doctor know if you have pheochromocytoma, a rare tumor that develops on a gland near the kidneys that can cause high blood pressure and a fast heartbeat.
Let your doctor know if you have any type of surgery planned, including dental surgery.
LOPRESSOR for Anxiety
Like many other beta blockers, LOPRESSOR is sometimes used off-label to control anxiety, including occasional performance anxiety and various anxiety disorders.
Talk to your doctor before taking LOPRESSOR or any other drug for anxiety. There may be another medication that’s safer and better suited to manage your anxiety.
LOPRESSOR and Pregnancy
Let your doctor know if you are pregnant, might become pregnant, or are breastfeeding before taking LOPRESSOR.
There’s not enough evidence to say that LOPRESSOR is safe during pregnancy, and pregnant women should take it only if there is a clear need.
LOPRESSOR could also pass into breast milk, so ask your doctor about breastfeeding before taking LOPRESSOR.
There’s no evidence that LOPRESSOR is safe or effective in children younger than 6 years old.
Common side effects of LOPRESSOR include:
- Dizziness or lightheadedness
- Dry mouth
- Stomach pain
- Gas or bloating
- Rash or itching
- Cold hands and feet
- Runny nose
Serious side effects can also occur.
If you have any of these side effects, stop taking LOPRESSOR and call your doctor right away:
- Shortness of breath
- Swelling of the hands, feet, ankles, or lower legs
- Unusual weight gain
- Rapid, pounding, or irregular heartbeat
Interactions with this medication
Many drugs may affect the way LOPRESSOR works, and LOPRESSOR could also affect how other drugs work.
It’s very important to let your doctor know about everything you are taking, even illegal drugs and any over-the-counter (OTC) vitamins, herbs, or dietary supplements.
Types of drugs that interact with LOPRESSOR include:
- Antidepressants including bupropion (Wellbutrin), fluoxetine (Prozac, Sarafem), and paroxetine (Paxil)
- Antimalaria drugs such as hydroxychloroquine
- Medications used to treat heartburn or other stomach conditions, such as cimetidine (Tagamet) and ranitidine (Zantac)
- Some heart medications, including clonidine (Catapres), propafenone (Rythmol), and quinidine (Quinaglute, Quinidex)
- Antihistamines like diphenhydramine (Benadryl)
- Certain HIV drugs, including ritonavir (Norvir)
- Some antifungal medications, including terbinafine (Lamisil)
- Certain drugs used to treat mental illness, including thioridazine (Mellaril)
LOPRESSOR and Alcohol
You should avoid drinking alcohol while taking LOPRESSOR.
Alcohol can make the side effect of drowsiness worse.
Other LOPRESSOR Interactions
It’s important to know that LOPRESSOR could make you feel sleepy. Don’t drive or operate machinery until you know how the drug affects you.
Your doctor may also tell you to stick to a low-sodium diet. Be sure to follow these instructions carefully.
Proper Use of this medication
LOPRESSOR is available as a tablet in standard doses of 50 and 100 milligrams (mg).
The drug is also available as an extended-release tablet in doses of 25, 50, 100, and 200 mg, in both the generic form and under the brand names Lopressor and Toprol XL.
Usually, the first dose of LOPRESSOR is 100 mg a day taken in either one or two doses.
Your doctor may gradually increase this dose. For people taking the long-acting Toprol XL tablets, the initial dose ranges from 25 to 100 mg once a day.
Although you can split the long-acting tablets, swallow the pills whole. Don’t crush or chew LOPRESSOR.
Do not take more LOPRESSOR than your doctor has prescribed.
If you do take too much of the drug, symptoms of a LOPRESSOR overdose may include:
- Trouble breathing or swallowing
- Swelling of the hands, feet, ankles, or lower legs
If you or someone else has symptoms of an overdose, call a poison control center.
If someone collapses or isn’t breathing, call 911.
Missed Dose of LOPRESSOR
Don’t stop taking LOPRESSOR without talking to your doctor.
If you suddenly stop taking the drug, you may develop rebound high blood pressure. Your doctor should decrease your dose of the drug gradually.
If you accidentally miss a dose of LOPRESSOR, take the missed dose as soon as you remember it.
If it’s almost time for your next dose, however, skip the missed dose.
Don’t make up for a missed dose by taking twice as much at one time.