Namenda Interactions: Alcohol, Medications, and Others

Does Namenda interact with other drugs?

Before you start taking Namenda, tell your doctor and pharmacist about any prescription, over-the-counter, or other drugs you take. Sharing this information with them may help prevent possible interactions. (To learn whether Namenda interacts with herbs, vitamins, or supplements, see the “Are there other interactions with Namenda?” section.)

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

The table below lists drugs that may interact with Namenda. Keep in mind that this table does not include all drugs that may interact with Namenda. For more information about some of these interactions, see the “Drug interactions explained” section.

When should I avoid Namenda?

Certain health conditions or other factors could raise your risk of harm if you take Namenda. In such cases, your doctor may not prescribe Namenda for you. These warnings are known as contraindications. The list below includes Namenda contraindications.

If you’ve had an allergic reaction: If you’ve had an allergic reaction to Namenda or any of its ingredients, your doctor likely won’t prescribe Namenda for you. This is because taking the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better options for you.

Before you start taking Namenda, talk with your doctor if any of the factors above apply to you. Your doctor can determine whether Namenda is safe for you to take.

Does Namenda interact with alcohol?

Namenda is not known to interact with alcohol. But your doctor may advise you to avoid or minimize alcohol consumption if you have Alzheimer’s disease, which is the condition Namenda is used to treat.

Alcohol affects your brain in ways that could worsen Alzheimer’s disease. So while alcohol doesn’t directly affect how well Namenda works, consuming it could worsen your Alzheimer’s disease symptoms.

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

Drug interactions explained

Learn more about certain drug interactions that can occur with Namenda.

Interaction with anticholinergics

Namenda can interact with anticholinergics, which are used to treat a variety of health conditions including overactive bladder and chronic obstructive pulmonary disease (COPD).

Examples of anticholinergic medications include:

• benztropine
• diphenhydramine (Benadryl)
• glycopyrrolate (Cuvposa)
• solifenacin (Vesicare)
• trospium

What could happen

Taking Namenda with anticholinergics can increase the risk of side effects from anticholinergics, such as dry mouth, constipation, and memory problems. It may also make Namenda less effective.

What you can do

If you take Namenda with an anticholinergic medication, your doctor may prescribe a dosage of the anticholinergic medication that’s lower than usual. You should not take a higher dose of either medication than your doctor prescribes. Your doctor will also closely monitor you to check that Namenda is working as intended. If Namenda is less effective than usual, they may recommend you stop taking the anticholinergic medication.

If you have questions about taking Namenda with anticholinergic medications, talk with your doctor or pharmacist.

Interaction with metformin and treatments that contain it

Namenda can interact with metformin and treatments that contain it. These treatments are used to treat type 2 diabetes.

Examples of medications that contain metformin include:

• metformin (Fortamet, Glumetza)
• Invokamet (canagliflozin/metformin)
• Synjardy (empagliflozin/metformin)
• Janumet XR (metformin/sitagliptin)
• glyburide/metformin

What could happen

Taking Namenda and metformin can increase the risk for side effects of Namenda or metformin. Your body uses your kidneys to get rid of both Namenda and metformin. Namenda and metformin can compete with one another for attention from your kidneys. This can result in your kidneys prioritizing eliminating one medication or the other, which can cause levels of one medication to rise in your body.

What you can do

Even though Namenda and metformin interact, these medications are still frequently prescribed together. Side effects from this interaction aren’t common. If your doctor prescribes you Namenda and metformin together, they will closely monitor you for side effects from either medication.

It is possible that metformin may cause a side effect called lactic acidosis. If you experience symptoms such as exhaustion, fatigue, muscle pains or cramps, or body weakness, call your doctor right away. If you experience these symptoms along with confusion, trouble breathing, or jaundice, call 911 or go to the closest emergency room. These symptoms may be a sign of a medical emergency related to lactic acidosis.

Interaction with certain antiarrhythmic drugs

Namenda can interact with certain antiarrhythmic drugs, which are used to treat arrhythmia (irregular heart rhythm).

Specifically, Namenda can interact with the antiarrhythmic drugs quinidine and dofetilide (Tikosyn).

What could happen

Taking Namenda with either quinidine or dofetilide can increase the risk of side effects from Namenda or side effects from dofetilide or quinidine. Your body relies on your kidneys to get rid of Namenda, quinidine, and dofetilide after you take a dose. Namenda, quinidine, and dofetilide all use the same pathway in the kidneys to exit your body. Namenda can compete with dofetilide or quinidine for this pathway in the kidneys, which can result in a higher level of Namenda or one of the antiarrhythmic medications in your system. This raises the risk of side effects.

What you can do

Due to this interaction, your doctor may prefer to prescribe an antiarrhythmic medication besides quinidine or dofetilide if you take Namenda. Or they may monitor you closely for side effects of Namenda or the antiarrhythmic medication.

Are there other interactions with Namenda?

Namenda may have other interactions. They could occur with supplements, foods, vaccines, or even lab tests. See below for details. Note that this information does not include all other possible interactions with Namenda.

Does Namenda interact with supplements?

Before you start taking Namenda, talk with your doctor and pharmacist about any herbs, vitamins, or supplements you take. Sharing this information with them may help you avoid possible interactions.

If you have questions about interactions that may affect you, talk with your doctor or pharmacist.

Namenda and herbs

There are currently no reports of Namenda interacting with herbs. But this doesn’t mean that interactions with herbs won’t be recognized in the future.

For this reason, it’s still important to check with your doctor or pharmacist before taking any of these products while taking Namenda.

Namenda interactions with vitamins and minerals

Namenda can interact with the following minerals found in some supplements:

• potassium bicarbonate
• potassium chloride
• potassium citrate
• sodium bicarbonate

These minerals can increase the pH of your urine. Increased urine pH can cause the level of Namenda in your system to increase, which raises your risk of Namenda side effects.

The minerals above are found in individual supplements and may also be found in certain multivitamins. If you take a multivitamin, ask your doctor or pharmacist to check if any ingredients interact with Namenda.

Does Namenda interact with food?

There are currently no reports of Namenda interacting with food. If you have questions about eating certain foods during your treatment with Namenda, talk with your doctor.

Note: Although Namenda can interact with potassium chloride in supplements, potassium salts are not expected to interact with Namenda. The amount of potassium chloride in supplements is higher than what is found in potassium chloride salts used in food.

Does Namenda interact with vaccines?

There are currently no reports of Namenda interacting with vaccines. If you have questions about getting certain vaccines during your Namenda treatment, talk with your doctor.

Does Namenda interact with lab tests?

There are currently no reports of Namenda interacting with lab tests. If you have questions about having certain lab tests done during your treatment with Namenda, talk with the healthcare professional ordering the test.

Does Namenda interact with cannabis or CBD?

There are currently no reports of Namenda interacting with cannabis (commonly called marijuana) or cannabis products such as cannabidiol (CBD). But as with any drug or supplement, talk with your doctor before using cannabis with Namenda.

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

Does my health history affect whether I should take Namenda?

Certain medical conditions or other health factors may raise the risk of interactions with Namenda. Before taking Namenda, talk with your doctor about your health history. They’ll determine whether Namenda is right for you.

Health conditions or other factors that might interact with Namenda include:

Active urinary tract infection: If you have an active urinary tract infection (UTI), your doctor may want to treat it before prescribing Namenda for you. A severe UTI can increase the pH of your urine, which can raise your risk of Namenda side effects.

Seizures: It’s not known whether it’s safe to take Namenda if you experience seizures. Your doctor can help determine whether it’s safe for you to take Namenda. They may want to monitor you closely for worsening seizure symptoms if they prescribe the medication for you.

Severe kidney condition: Your body relies on your kidneys to get rid of Namenda after you take a dose. If you have a severe kidney condition, such as kidney failure, the amount of Namenda in your system may build up. This can raise your risk of side effects from Namenda. Your doctor can provide more information on the severity of your kidney condition and help you determine whether it’s safe to take Namenda.

Severe liver condition: It’s not known whether it’s safe to take Namenda if you have a severe liver condition, such as liver failure. Talk with your doctor to learn more about the risks and benefits of taking Namenda based on the severity of your liver condition.

Tobacco use: Your body uses your kidneys to get rid of both Namenda and nicotine, including the nicotine found in tobacco products. Using tobacco while taking Namenda can increase the level of Namenda in your body, which raises your risk of side effects that the medication may cause. Your doctor can provide information on ways to help you quit smoking or using tobacco to avoid this interaction.

Pregnancy: It’s not known whether Namenda is safe to take during pregnancy. If you’re pregnant or planning a pregnancy, talk with your doctor before taking Namenda.

Breastfeeding: It’s not known whether it’s safe to take Namenda while breastfeeding. It isn’t known if the drug passes into breast milk or whether the drug may cause side effects in a child who’s breastfed. If you’re breastfeeding or planning to breastfeed, talk with your doctor about your options.

Allergic reaction: If you’ve had an allergic reaction to Namenda or any of its ingredients, your doctor will likely not prescribe Namenda. This is because taking the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better choices for you.

How can I prevent interactions?

Taking certain steps can help you avoid interactions with Namenda. Before starting treatment, talk with your doctor and pharmacist. Things to discuss with them include:

• whether you drink alcohol or use cannabis
• other medications you take, as well as any vitamins, supplements, and herbs (they can also help you fill out a medication list)
• what to do if you start taking a new drug during your Namenda treatment

It’s also important to understand Namenda’s label and other paperwork that may come with the drug. Colored stickers that describe interactions may be on the label. And the paperwork (sometimes called the patient package insert or medication guide) may have other details about interactions. (If you did not get paperwork with Namenda, ask your pharmacist to print a copy for you.)

If you have trouble reading or understanding this information, your doctor or pharmacist can help.

Taking Namenda exactly as prescribed can also help prevent interactions.

Disclaimer: Healthline 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.