Lopressor interactions: Alcohol, supplements, and more

Lopressor (metoprolol tartrate) is a brand-name oral tablet that’s prescribed for high blood pressure and certain heart conditions in adults. Lopressor has interactions with some drugs, including other heart-related medications such as calcium channel blockers.

An interaction occurs when one substance causes another substance to have a different effect than expected.

To learn more about Lopressor’s interactions, keep reading. For additional information about Lopressor, including details about its uses, see this article.

In some cases, factors or conditions could prevent your doctor from prescribing Lopressor due to the risk of harm. These are known as contraindications. The Lopressor contraindications include:

Doctors typically will not prescribe Lopressor for people with certain heart or blood vessel problems. This is because Lopressor may worsen these conditions.

The exact heart or blood vessel problem can vary depending on the condition you’re taking Lopressor to treat. A few examples include:

If you have a heart or blood vessel problem, your doctor can tell you whether Lopressor is a safe treatment option.

If you’ve had an allergic reaction to Lopressor, any of its ingredients, or another beta-blocker, your doctor will likely not prescribe Lopressor. Taking the drug could cause another allergic reaction. You can ask them about other treatments that may be better for you.

Note: Before you start treatment with Lopressor, it’s important to tell your doctor if these contraindications apply to you. They can determine whether to prescribe Lopressor.

There are no known interactions between Lopressor and alcohol.

However, drinking large amounts of alcohol can increase your blood pressure. Lopressor can be used to treat high blood pressure. So consuming alcohol while taking Lopressor for this use may make it hard to tell if the drug is working.

If you have questions about drinking alcohol while taking Lopressor, talk with your doctor or pharmacist.

Before you start treatment with Lopressor, tell your doctor and pharmacist which prescription, over-the-counter, and other medications you take. By sharing this information with them, you may help prevent possible interactions. To learn whether Lopressor interacts with supplements, herbs, or vitamins, see the “Lopressor and other interactions” section below.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Here’s a table of drugs that can interact with Lopressor. Keep in mind that this table doesn’t include all drugs that may interact with Lopressor. Some of these interactions are described in detail just below in “Drug interactions in depth.”

Here’s a closer look at certain drug interactions of Lopressor.

Hydralazine is a vasodilator prescribed to treat high blood pressure.

Interaction result. Taking Lopressor with hydralazine can increase the risk of side effects from Lopressor.

Interaction explained. Hydralazine slows the breakdown of Lopressor in your body. As a result, taking Lopressor with hydralazine can raise the level of Lopressor in your body. This may increase your risk of side effects from Lopressor.

Steps you or your doctor may take. Before starting Lopressor treatment, tell your doctor if you take hydralazine. They can advise you on whether it’s safe to take these medications together.

Clonidine (Catapres-TTS, Nexiclon XR, Kapvay) is a type of blood pressure medication called a central agonist. It’s prescribed to treat high blood pressure and attention deficit hyperactivity disorder (ADHD).

Interaction result. Taking Lopressor with clonidine can increase the risk of side effects from either drug.

Interaction explained. When taken individually, both Lopressor and clonidine may cause side effects that include slow heart rate and low blood pressure. Taking Lopressor with clonidine may lower your heart rate or blood pressure even further.

Steps you or your doctor may take. Before taking Lopressor, be sure your doctor knows if you’re taking clonidine. They can recommend whether it’s safe to take these medications together.

Diphenhydramine (Benadryl) is an antihistamine prescribed to ease symptoms of allergies and other conditions.

Interaction result. Taking Lopressor with diphenhydramine can increase the risk of side effects from Lopressor.

Interaction explained. Diphenhydramine slows down the activity of an enzyme called cytochrome P450 2D6 (CYP2D6). An enzyme is a type of protein.

CYP2D6 helps break down Lopressor in the body. Taking Lopressor with diphenhydramine can raise the level of Lopressor in your system. This may increase your risk of side effects from Lopressor.

Steps you or your doctor may take. Diphenhydramine is available over the counter (OTC), meaning you don’t need a prescription to purchase it. The drug is available by itself and in combination with other drugs in many OTC cold medications.

If you need to ease symptoms of allergies while taking Lopressor, talk with your doctor or pharmacist. They can recommend medications that are safe to take with Lopressor.

Lopressor may have other interactions, such as with supplements, foods, vaccines, or even lab tests. You’ll find details below. Keep in mind that the following information does not include all other possible interactions with Lopressor.

It’s possible for drugs to interact with supplements such as vitamins and herbs.

There are no specific reports of herbs interacting with Lopressor. However, that doesn’t mean herbal interactions won’t occur or be recognized in the future. Because of this, it’s important to check with your doctor or pharmacist before taking any of these products during Lopressor treatment.

There are no specific reports of vitamins interacting with Lopressor. However, that doesn’t mean vitamin interactions won’t occur or be recognized in the future. Because of this, you should talk with your doctor or pharmacist before taking any vitamin product with Lopressor.

There were no reports of food interactions with Lopressor. If you’d like to learn more about eating certain foods during treatment with Lopressor, talk with your doctor.

There are no specific reports of vaccines interacting with Lopressor. To learn more about getting specific vaccines while taking Lopressor, talk with your doctor.

There are no specific reports of lab tests interacting with Lopressor. To learn more about getting certain lab tests while taking Lopressor, talk with your doctor.

Cannabis (often called marijuana) and cannabis products, such as cannabidiol (CBD), have not been specifically reported to interact with Lopressor. However, as with any drug or supplement, talk with your doctor before using cannabis in combination with Lopressor. The impact of cannabis may affect how well you stick to your Lopressor treatment plan.

Note: Cannabis is illegal at a federal level but is legal in many states to varying degrees.

Certain medical conditions and other factors may increase the risk of interactions with Lopressor. Before you take this drug, be sure to talk with your doctor about your health history. Lopressor may not be the right treatment option if you have certain medical conditions or other factors affecting your health.

Health conditions or factors that might interact with Lopressor include:

You can take certain steps to help prevent interactions with Lopressor. Your doctor and pharmacist are key resources, so reach out to them before starting treatment. They can tell you whether there are special instructions for preventing interactions with Lopressor.

For example, you should plan to do the following:

It’s also important to read the Lopressor label and other paperwork that may come with the drug. The label may have colored stickers that mention an interaction. And the paperwork, sometimes called the medication guide or patient package insert, may contain details about interactions.

If Lopressor doesn’t come with paperwork, you can ask your pharmacist to print a copy. If you need help reading or understanding this information, ask your doctor or pharmacist.

You can also help prevent interactions with Lopressor by taking it exactly as your doctor prescribes.

Besides learning about interactions, you may want to find out more about Lopressor. These resources might help:

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.