Generic name: memantine [ me-MAN-teen ]
Drug class: Miscellaneous central nervous system agents

Medically reviewed by Drugs.com. Last updated on May 27, 2022.

Uses for memantine

Memantine is used to treat moderate to severe Alzheimer's disease. Memantine is not a cure for Alzheimer's disease but it can help people with the disease. Memantine will not cure Alzheimer's disease, and it will not stop the disease from getting worse.

This medicine is available only with your doctor's prescription.

Before using memantine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies on the relationship of age to the effects of memantine have not been performed in the pediatric population.

Geriatric

No information is available on the relationship of age to the effects of memantine in geriatric patients.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Acetazolamide
• Amantadine
• Brinzolamide
• Bupropion
• Dextromethorphan
• Dorzolamide
• Ketamine
• Methazolamide
• Methotrexate
• Sodium Bicarbonate

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Epilepsy or seizures or
• Urinary tract problems (e.g., bladder problems, difficulty with urination)—Use with caution. May make these conditions worse.

• Kidney disease or
• Liver disease—Use with caution. The effects may be increased because of slower removal of the medicine from the body.

Proper use of memantine

Take this medicine exactly as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

This medicine comes with a patient information insert. Read and follow the instructions in the insert carefully. Ask your doctor if you have any questions.

You may take this medicine with or without food.

Swallow the extended-release capsules whole. Do not break, crush, or chew them.

If you cannot swallow the extended-release capsule, you may open it and pour the medicine into a small amount of soft food such as applesauce. Stir this mixture well and swallow it without chewing.

For patients taking the oral liquid:

• Remove the oral dosing syringe along with the cap and plastic tube from the bag and attach to tube to the cap.
• Open the child-resistant cap on the bottle by pushing down on the cap while turning the cap counter-clockwise (to the left) and remove the cap and seal from the bottle.
• Insert the plastic tube fully into the bottle and screw the cap tightly onto the bottle by turning the cap clockwise (to the right).
• Keeping the bottle upright on the table, remove the lid to uncover the opening on the top of the cap. With the plunger fully depressed, insert the tip of the syringe firmly into the opening of the cap.
• While holding the syringe, gently pull the plunger of the syringe up to draw medicine into the syringe.
• Remove the syringe from the cap opening. Invert the syringe (point tip upwards) and slowly press the plunger to a level that pushed out any large air bubbles that may be present. Keep the plunger in this position.
• Re-insert the tip of the syringe into the cap opening. While holding the syringe, continue to gently pull out the plunger until the bottom of the black ring of the plunger reaches the appropriate mark on the syringe that corresponds to the dose prescribed.
• Remove the syringe from the bottle and swallow the oral solution directly from the syringe. Do not mix with any other liquid.
• After use, reseal the bottle by snapping the attached lid closed.
• Rinse the empty syringe by inserting the open end of the syringe into a glass of water, pulling the plunger out to draw in water, and pushing the plunger in to remove the water. Repeat several times. Allow the syringe to air dry.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For treatment of Alzheimer's disease:
  • For oral dosage form (extended-release capsules):
    • Adults—At first, 7 milligrams (mg) once a day. Your doctor may gradually increase your dose as needed. However, the dose is usually not more than 28 mg per day.
    • Children—Use and dose must be determined by your doctor.
  • For oral dosage form (solution and tablets):
    • Adults—At first, 5 milligrams (mg) once a day. Your doctor may gradually increase your dose as needed. However, the dose is usually not more than 10 mg two times a day.
    • Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions while using memantine

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check for unwanted effects.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects of memantine

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Less common

• Bloating or swelling of the face, arms, hands, lower legs, or feet
• blurred vision
• dizziness
• headache
• nervousness
• pounding in the ears
• rapid weight gain
• slow or fast heartbeat
• tingling of the hands or feet
• unusual weight gain or loss

Incidence not known

• Abdominal or stomach pain
• agitation
• black, tarry stools
• bleeding gums
• blistering, peeling, or loosening of the skin
• blood in the urine or stools
• chest pain
• coma
• constipation
• continuing vomiting
• convulsions
• dark-colored urine
• decreased urine output
• depression
• fainting
• fast, pounding, or irregular heartbeat or pulse
• general feeling of tiredness or weakness
• high fever
• high or low blood pressure
• hostility
• increased sweating
• indigestion
• infection from breathing foreign substances into the lungs
• itching
• lethargy
• light-colored stools
• lip smacking or puckering
• loss of consciousness
• muscle twitching
• no blood pressure
• no breathing
• no pulse
• numbness or tingling in the face, arms, or legs
• pain in the stomach, side, or abdomen, possibly radiating to the back
• pain or swelling in the arms or legs without any injury
• pain, tension, and weakness upon walking that subsides during periods of rest
• pinpoint red spots on the skin
• pounding, slow heartbeat
• puffing of the cheeks
• rapid or worm-like movements of the tongue
• rapid weight gain
• recurrent fainting
• red irritated eyes
• red skin lesions, often with a purple center
• seizures
• severe constipation
• severe headache
• severe muscle stiffness
• severe vomiting
• sores, ulcers, or white spots in the mouth or on the lips
• stupor
• sudden severe weakness
• swelling of the face, ankles, or hands
• total body jerking
• trouble with speaking or walking
• troubled breathing
• twitching, twisting, or uncontrolled repetitive movements of the tongue, lips, face, arms, or legs
• uncontrolled chewing movements
• unusual bleeding or bruising
• unusually pale skin
• vomiting
• yellow eyes and skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

• Confusion

Less common

• Anxiety
• back pain
• bladder pain
• bloody or cloudy urine
• change in walking and balance
• chills
• clumsiness or unsteadiness
• cough producing mucus
• coughing
• diarrhea
• difficult, burning, or painful urination
• difficulty with breathing
• difficulty with moving
• discouragement
• dry mouth
• fear
• feeling sad or empty
• fever
• frequent urge to urinate
• general feeling of discomfort or illness
• hyperventilation
• insomnia
• irritability
• joint pain
• loss of appetite
• loss of bladder control
• loss of interest or pleasure
• lower back or side pain
• muscle pain or stiffness
• nausea
• nervousness
• pain
• pain in the joints
• restlessness
• seeing, hearing, or feeling things that are not there
• shortness of breath
• sleepiness or unusual drowsiness
• sore throat
• tightness in the chest
• tiredness
• trouble with concentrating
• trouble with sleeping
• unusual tiredness or weakness
• vomiting
• wheezing

Incidence not known

• Burning feeling in the chest or stomach
• burning, numbness, pain, or tingling in all fingers except smallest finger
• cold sweats
• cool pale skin
• decreased interest in sexual intercourse
• difficulty with swallowing
• general feeling of discomfort or illness
• heartburn
• inability to have or keep an erection
• increased hunger
• large amounts of fat in the blood
• loss in sexual ability, desire, drive, or performance
• nightmares
• shakiness
• slurred speech
• stomach cramps
• stomach upset
• tenderness in the stomach area
• watery or bloody diarrhea

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer