Memantine ER 7mg Capsules
It is used to treat dementia in people with Alzheimer's disease.
Drug Class
Agent for Alzheimer's Disease
Pharmacologic Class
N-methyl-D-aspartate (NMDA) receptor antagonist
Pregnancy Category
Category B
FDA Approved
Jun 2010
DEA Schedule
Not Controlled
Overview
What is this medicine?
Memantine ER is a medication used to treat moderate to severe Alzheimer's disease. It works by helping to balance certain natural substances in the brain, which can improve memory, awareness, and the ability to perform daily activities. It is an extended-release capsule, meaning it releases the medicine slowly over time, allowing for once-daily dosing.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. You can take this medication with or without food. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
It's essential to swallow the medication whole; do not chew or crush it. If you notice any capsules that appear abnormal or are damaged, do not take them. If you have difficulty swallowing the medication whole, you can sprinkle the contents onto applesauce. If you choose to do this, swallow the mixture immediately without chewing.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. Dispose of any unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also want to check if there are any drug take-back programs available in your area.
What to Do If You Miss a Dose
If you miss a dose, skip it and take your next dose at the scheduled time. Do not take two doses at once or take extra doses. If you miss taking your medication for several days in a row, contact your doctor before restarting your medication regimen.
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. You can take this medication with or without food. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
It's essential to swallow the medication whole; do not chew or crush it. If you notice any capsules that appear abnormal or are damaged, do not take them. If you have difficulty swallowing the medication whole, you can sprinkle the contents onto applesauce. If you choose to do this, swallow the mixture immediately without chewing.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. Dispose of any unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also want to check if there are any drug take-back programs available in your area.
What to Do If You Miss a Dose
If you miss a dose, skip it and take your next dose at the scheduled time. Do not take two doses at once or take extra doses. If you miss taking your medication for several days in a row, contact your doctor before restarting your medication regimen.
Lifestyle & Tips
- Take the capsule once daily at approximately the same time each day.
- Swallow the capsule whole. Do not crush, chew, or divide the capsule.
- If you have difficulty swallowing, the capsule may be opened and the entire contents sprinkled on a small amount of applesauce. Swallow the mixture immediately without chewing. Do not store the mixture for later use.
- Memantine ER can be taken with or without food.
- Do not stop taking memantine without consulting your doctor, as symptoms may worsen.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
Initial 7 mg once daily, titrated weekly by 7 mg increments to a target maintenance dose of 28 mg once daily.
Dose Range:
7 - 28 mg
Condition-Specific Dosing:
moderateToSevereAlzheimersDisease:
Initial 7 mg once daily, titrated weekly by 7 mg increments to a target maintenance dose of 28 mg once daily. Max dose 28 mg/day.
switchingFromImmediateRelease:
Patients on memantine IR 10 mg twice daily can be switched to memantine ER 28 mg once daily the day after the last IR dose. For other IR doses, initiate ER titration at 7 mg once daily.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No adjustment (CrCl 50-80 mL/min)
Moderate:
Maximum dose 14 mg once daily (CrCl 30-49 mL/min)
Severe:
Maximum dose 14 mg once daily (CrCl 5-29 mL/min)
Dialysis:
Not specifically studied; use with caution, likely similar to severe impairment.
Hepatic Impairment:
Mild:
No adjustment
Moderate:
No adjustment
Severe:
Not studied; use with caution.
Pharmacology
Mechanism of Action
Memantine is a non-competitive, moderate-affinity N-methyl-D-aspartate (NMDA) receptor antagonist. It is believed to exert its therapeutic effect by blocking the effects of abnormal excitatory glutamate, which is thought to contribute to the pathophysiology of Alzheimer's disease, without interfering with normal physiological NMDA receptor function.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 100%
Tmax:
9-12 hours (extended-release)
FoodEffect:
Minimal effect on absorption; can be taken with or without food.
Distribution:
Vd:
Approximately 9-11 L/kg
ProteinBinding:
Approximately 45%
CnssPenetration:
Yes
Elimination:
HalfLife:
Approximately 60-80 hours (extended-release)
Clearance:
Primarily renal clearance
ExcretionRoute:
Urine
Unchanged:
Approximately 48% (of immediate-release dose)
Pharmacodynamics
OnsetOfAction:
Gradual, due to titration schedule
PeakEffect:
Achieved after reaching maintenance dose and steady-state concentrations (typically several weeks)
DurationOfAction:
24 hours (due to extended-release formulation and long half-life)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
If you experience any of the following symptoms, call your doctor or seek medical attention immediately, as they may be signs of a severe and potentially life-threatening side effect:
- Signs of an allergic reaction, such as rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat
- Feeling confused
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. Contact your doctor or seek medical help if you experience any of the following side effects or if they bother you or do not go away:
- Dizziness or headache
- Diarrhea or constipation
Important Note
This list does not include all possible side effects. If you have questions or concerns about side effects, consult your doctor. For medical advice about side effects, you can also contact your doctor. Additionally, you can report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
If you experience any of the following symptoms, call your doctor or seek medical attention immediately, as they may be signs of a severe and potentially life-threatening side effect:
- Signs of an allergic reaction, such as rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat
- Feeling confused
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. Contact your doctor or seek medical help if you experience any of the following side effects or if they bother you or do not go away:
- Dizziness or headache
- Diarrhea or constipation
Important Note
This list does not include all possible side effects. If you have questions or concerns about side effects, consult your doctor. For medical advice about side effects, you can also contact your doctor. Additionally, you can report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe dizziness or lightheadedness
- Severe confusion or disorientation
- Hallucinations (seeing or hearing things that are not there)
- Seizures
- Severe constipation or difficulty urinating
- Unusual weakness or tiredness
- Signs of an allergic reaction (e.g., rash, itching, swelling, severe dizziness, trouble breathing)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. This information will help your doctor and pharmacist assess potential interactions between this medication and other substances you are taking.
* Any existing health problems, as this medication may interact with certain conditions or exacerbate underlying health issues.
To ensure your safety, it is crucial to verify that this medication can be taken in conjunction with your other medications and health conditions. Do not initiate, discontinue, or modify the dosage of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. This information will help your doctor and pharmacist assess potential interactions between this medication and other substances you are taking.
* Any existing health problems, as this medication may interact with certain conditions or exacerbate underlying health issues.
To ensure your safety, it is crucial to verify that this medication can be taken in conjunction with your other medications and health conditions. Do not initiate, discontinue, or modify the dosage of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all of your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. If you are pregnant, planning to become pregnant, or are currently breast-feeding, you must discuss this with your doctor. This conversation will help you understand the potential benefits and risks of taking this drug, both for you and your baby, allowing you to make an informed decision.
Overdose Information
Overdose Symptoms:
- Agitation
- Confusion
- Hallucinations
- Seizures
- Somnolence
- Stupor
- Coma
- Hypertonia (increased muscle tone)
- Hyperreflexia (overactive reflexes)
- Vomiting
- Vertigo
- Aggression
- Ataxia (lack of coordination)
- Dizziness
- Headache
- Diarrhea
What to Do:
In case of suspected overdose, seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Management is symptomatic and supportive, including gastric lavage or activated charcoal if appropriate.
Drug Interactions
Major Interactions
- Other NMDA antagonists (e.g., amantadine, ketamine, dextromethorphan): Increased risk of CNS adverse reactions.
- Drugs that alkalinize urine (e.g., carbonic anhydrase inhibitors, sodium bicarbonate): Can decrease memantine renal clearance, leading to increased plasma levels and potential toxicity.
Moderate Interactions
- Drugs eliminated by renal tubular secretion (e.g., cimetidine, ranitidine, quinidine, procainamide): May reduce memantine clearance.
- Hydrochlorothiazide: May reduce memantine clearance.
Monitoring
Baseline Monitoring
Cognitive function assessment (e.g., MMSE, ADAS-Cog)
Rationale: To establish baseline cognitive status and assess disease severity.
Timing: Prior to initiation of therapy
Renal function (e.g., serum creatinine, eGFR/CrCl)
Rationale: Memantine is primarily renally eliminated; dose adjustments are required in renal impairment.
Timing: Prior to initiation of therapy
Routine Monitoring
Cognitive function assessment
Frequency: Periodically (e.g., every 6-12 months or as clinically indicated)
Target: Improvement or stabilization of cognitive symptoms
Action Threshold: Significant decline or lack of benefit may warrant re-evaluation of therapy.
Adverse effects monitoring (e.g., dizziness, headache, confusion, constipation, hypertension)
Frequency: Regularly, especially during titration and initial weeks of therapy
Target: Absence or mild, tolerable side effects
Action Threshold: Persistent or severe adverse effects may require dose reduction or discontinuation.
Renal function
Frequency: Periodically, especially in patients with pre-existing renal impairment or if clinical status changes.
Target: Stable renal function
Action Threshold: Significant decline in renal function may necessitate dose adjustment.
Symptom Monitoring
- Dizziness
- Headache
- Confusion
- Constipation
- Hypertension
- Hallucinations
- Somnolence
- Vomiting
- Diarrhea
- Agitation
Special Patient Groups
Pregnancy
Memantine is classified as Pregnancy Category B. Animal studies have not shown evidence of teratogenicity. There are no adequate and well-controlled studies in pregnant women. Use during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Limited human data; animal studies showed no teratogenicity.
Second Trimester:
Limited human data.
Third Trimester:
Limited human data.
Lactation
It is unknown whether memantine is excreted in human milk. Memantine is excreted in rat milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from memantine, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Infant Risk:
Risk unknown; caution advised due to potential for adverse effects.
Pediatric Use
Safety and efficacy have not been established in pediatric patients. Memantine is not indicated for use in children.
Geriatric Use
Memantine is primarily used in the geriatric population for Alzheimer's disease. No specific dose adjustment is required based on age alone, but age-related decline in renal function should be considered, and doses adjusted accordingly for renal impairment.
Clinical Information
Clinical Pearls
- Memantine ER offers once-daily dosing, which may improve patient adherence compared to immediate-release formulations.
- Gradual dose titration is essential to minimize common side effects like dizziness and confusion.
- Capsules can be opened and sprinkled on applesauce for patients who have difficulty swallowing, but the beads must not be chewed.
- Often used in combination with cholinesterase inhibitors (e.g., donepezil) for moderate to severe Alzheimer's disease.
- Monitor for changes in cognitive function and behavioral symptoms, as well as for common adverse effects, especially during the initial titration phase.
Alternative Therapies
- Cholinesterase inhibitors (e.g., donepezil, rivastigmine, galantamine) for mild to moderate Alzheimer's disease or in combination with memantine for more advanced stages.
Cost & Coverage
Average Cost:
Highly variable; check current pricing per 30 capsules
Generic Available:
Yes
Insurance Coverage:
Tier 2 or Tier 3 (depending on insurance plan)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication, including the amount taken and the time it happened, to facilitate prompt and effective treatment.