Generic name: memantine (meh MAN teen)
Brand name: Namenda, Namenda XR
Dosage forms: oral capsule, extended release (14 mg; 21 mg; 28 mg; 7 mg); oral kit (extended release; immediate release); oral solution (2 mg/mL); oral tablet (10 mg; 5 mg)
Drug class: Miscellaneous central nervous system agents
Memantine reduces the actions of chemicals in the brain that may contribute to the symptoms of Alzheimer's disease.
Memantine is used to treat moderate to severe dementia of the Alzheimer's type.
Memantine may also be used for purposes not listed in this medication guide.
Warnings
Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.
Before taking this medicine
You should not use memantine if you are allergic to it.
To make sure memantine is safe for you, tell your doctor if you have:
- epilepsy or other seizure disorder;
- liver disease;
- kidney disease;
- urination problems; or
- a bladder or kidney infection.
memantine is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.
It is not known whether memantine passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.
How should I take memantine?
Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not take this medicine in larger or smaller amounts or for longer than recommended.
Memantine can be taken with or without food.
Do not crush, chew, break, or open an extended-release capsule. Swallow it whole.
To make swallowing easier, you may open the extended-release capsule and sprinkle the medicine into a spoonful of applesauce. Swallow right away without chewing. Do not save the mixture for later use.
Measure liquid medicine (oral solution) with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.
Do not mix the oral solution with any other liquids.
Rinse the empty oral syringe with clean water and allow it to air dry after every use.
Use memantine regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.
Your doctor will need to check your progress while you are using memantine.
Store memantine at room temperature away from moisture and heat. Keep the liquid medicine bottle tightly closed with the cap provided. Do not store the bottle with the oral syringe in it.
Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
If you miss doses or forget to take your medicine for several days, call your doctor before starting the medicine again.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid while taking memantine?
Memantine can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.
Memantine side effects
Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have:
- severe headache, blurred vision, pounding in your neck or ears;
- seizure (convulsions); or
- unusual changes in mood or behavior.
Common side effects may include:
- diarrhea;
- dizziness; or
- headache.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Memantine dosing information
Usual Adult Dose for Alzheimer's Disease:
IMMEDIATE-RELEASE:
Week 1: 5 mg orally once a day.
Week 2: 10 mg orally/day (Administer 5 mg twice a day.)
Week 3: 15 mg orally/day (Administer 5 mg and 10 mg as separate doses.)
Week 4/Maintenance Dose: 20 mg orally/day (Administer 10 mg twice a day.)
EXTENDED-RELEASE:
-Initial Dose: 7 mg orally once a day.
-Maintenance and Maximum Dose: 28 mg orally once a day; increase the initial dose in 7 mg increments to the recommended maintenance dose.
Comments: The minimum recommended interval between dose increases is one week; only increase dosage if the previous dose has been well tolerated.
Use: Treatment of moderate to severe dementia of the Alzheimer's type.
What other drugs will affect memantine?
Tell your doctor about all your current medicines and any you start or stop using, especially:
- amantadine;
- zonisamide;
- cough medicine that contains dextromethorphan (Delsym, Robitussin Maximum Strength, Vicks 44, and others);
- medicines to make the urine alkaline--urine sodium bicarbonate, potassium citrate (K-Lyte, Urocit-K), sodium citrate and citric acid (Bicitra, Oracit), or sodium citrate and potassium (Citrolith, Polycitra); or
- medicine to treat glaucoma or increased pressure inside the eyes--acetazolamide, methazolamide.
This list is not complete. Other drugs may interact with memantine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.