What are 4 key Namenda side effects to watch out for?

Key Points

• Namenda (memantine) is an oral tablet that may be used to treat moderate to severe dementia related to Alzheimer’s disease.
• Common side effects of Namenda include dizziness, headache, confusion, and constipation. However, many side effects reported during clinical studies were similar in frequency to those reported for the placebo group.
• The dose of Namenda should be started low and slowly increased over a month to lower your risk of side effects.

What is Namenda?

Namenda (memantine) is a N-methyl-D-aspartate (NMDA) receptor antagonist that may be used to treat moderate to severe dementia due to Alzheimer’s disease. Namenda comes as a tablet that’s taken by mouth twice daily. It’s started at a low dose taken once daily for one week, and then the dose is increased over the next few weeks to the maintenance dose. While it can help manage symptoms, it's important to be aware of the potential side effects.

4 side effects of Namenda and how to manage them

Let’s review 4 side effects* of Namenda that you should be aware of. Some side effects can be managed at home. We’ll offer some tips on what you should do if you experience side effects so that you can continue your treatment.

1. Dizziness

Dizziness was the most common side effect reported in clinical studies of Namenda, occurring in 7% of people who took it. This can lead to falls and other serious accidents. Don’t drive until you know how Namenda affects you.

Tips for managing dizziness

• Drink plenty of fluids
• If you feel dizzy, hold on to something stable or carefully sit down until it passes
• Stand up slowly from a sitting or lying position

Tell your doctor if you experience dizziness often after starting Namenda. They can evaluate you for other medical conditions that might be causing you to feel dizzy. If it’s due to Namenda, they might need to adjust your dose or switch you to a different medication.

2. Headache

It’s common to experience headaches from Namenda. About 6% of people who took Namenda in studies reported headache as a side effect. Headaches can negatively impact quality of life and make it hard to perform normal daily activities. While they might not be completely avoidable, there are some things you can do to manage them at home.

Tips for managing headaches

• Rest in a dark, quiet room
• Reduce stress by trying meditation or yoga
• Try an over-the-counter pain reliever, like acetaminophen (Tylenol)
• Use a warm or cold compress on your forehead
• Stay hydrated

If your headache seems severe or isn’t going away after taking pain medication, get medical attention.

3. Confusion

While confusion is a common symptom of Alzheimer’s disease, slightly more people reported it as a side effect while taking Namenda. In studies, 6% of people taking Namenda experienced confusion compared to 5% of people taking a placebo (no medication). No matter what’s causing confusion, a few changes can be made to help.

Tips for managing confusion

• Keep a regular routine for daily activities
• Don’t move familiar items around, like furniture or silverware
• Reduce clutter in your living environment
• Use labels to organize items

If you notice that you’re becoming confused more often, speak with your doctor. They can help you determine the cause and adjust your dose of Namenda accordingly.

4. Constipation

Namenda can sometimes cause or worsen constipation. About 5% of people taking Namenda will experience constipation. Making some changes to your diet may help prevent and treat constipation. There are also over-the-counter stool softeners and other medications that can help.

Tips for managing constipation

• Make sure you’re getting 25-35 grams of fiber daily by eating plenty of fruits, vegetables, whole grains, legumes, and nuts
• Drink water often
• Get regular physical activity, aiming for 30 minutes most days
• Establish a regular toilet routine
• Ask your doctor about over-the-counter products, like fiber supplements and stool softeners

If you don’t already get enough fiber in your diet, it’s important to introduce more fiber slowly. If you eat too much fiber too quickly, you could experience gas and cramping. Contact your doctor if your constipation isn’t getting better, or if you have bloating and stomach pain.

* This is not a complete list of side effects. See here for more information.