memantine
Brand names: Namenda
Memantine is a medicine used to treat moderate to severe Alzheimer's disease. It may help with memory and thinking.
Drug Shortage Alert
memantine is currently listed as to be discontinued by the FDA. Affected manufacturer: Upsher-Smith Laboratories, LLC.
View all drug shortages →Drug Pricing (NADAC)
Generic Price
$0.32/unit
Generic Available
Yes (31 manufacturers)
Pricing data from NADAC (CMS), effective December 18, 2024. Compare all drug costs →
What it does
Memantine is used to treat moderate to severe Alzheimer's disease.
Common side effects
Dizziness, Headache, Confusion
Key warnings
If you have conditions that make your urine less acidic (more alkaline), memantine levels in your blood may increase.
How It Works
Memantine is an NMDA receptor antagonist. This means it blocks the effects of a chemical in the brain called glutamate. By blocking glutamate, memantine may help protect brain cells from damage.
How to Take It
Start by taking 5 mg of memantine once a day. Your doctor may increase the dose by 5 mg each week. The usual effective dose is 10 mg twice a day. You can take memantine with or without food.
Pregnancy & Breastfeeding
It is not known if memantine can harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if memantine passes into breast milk, so talk to your doctor if you are breastfeeding.
Missed Dose
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses at the same time.
Storage
Store memantine tablets at room temperature, between 68° to 77°F (20° to 25°C).
Side Effects (from patient reports)
Based on 6,643 FDA adverse event reports.
FDA Adverse Event Report Analysis
Detailed analysis of 12,807 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2004–2025.
Total Reports
12,807
Death-Related Reports
1,934
Hospitalization Reports
5,255
Top Indication
Product Used For Unknown Indication
Gender Distribution
Age Distribution
Most Reported Adverse Reactions (FAERS)
| # | Reaction | Reports |
|---|---|---|
| 1 | FALL | 937 |
| 2 | DEATH | 853 |
| 3 | DRUG INEFFECTIVE | 811 |
| 4 | OFF LABEL USE | 740 |
| 5 | CONFUSIONAL STATE | 706 |
| 6 | FATIGUE | 605 |
| 7 | HALLUCINATION | 581 |
| 8 | CONDITION AGGRAVATED | 502 |
| 9 | ASTHENIA | 469 |
| 10 | SOMNOLENCE | 438 |
| 11 | DIZZINESS | 436 |
| 12 | URINARY TRACT INFECTION | 420 |
| 13 | NAUSEA | 404 |
| 14 | DIARRHOEA | 379 |
| 15 | GAIT DISTURBANCE | 346 |
Reactions in Death Reports
Reactions in Hospitalization Reports
Source: FDA FAERS (Adverse Event Reporting System) FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation
Serious Warnings
If you have conditions that make your urine less acidic (more alkaline), memantine levels in your blood may increase. This could increase the risk of side effects. Talk to your doctor if you have kidney problems or take medicines that affect urine pH.
Known Drug Interactions
7.2 Use with Other N-methyl-D-aspartate (NMDA) Antagonists The combined use of memantine hydrochloride with other NMDA antagonists (amantadine, ketamine, and dextromethorphan) has not been systematically evaluated and such use should be approached with caution.
Mechanism: Both of these drugs affect the same receptors in the brain, and using them together has not been well studied. This could cause unknown side effects or change how the medications work.
What to do: Use this combination with caution and only if your doctor says it is necessary. Watch for any unusual changes in how you feel and report them to your provider.
Cases of interactions with other OCT2 substrates, memantine and metformin, have also been reported.
Mechanism: Both drugs use the same pathway in the kidneys to leave the body. This can cause memantine to build up in the blood because the kidneys are busy processing the trimethoprim.
What to do: Your doctor should monitor you for increased side effects from memantine while taking these together.
Common Questions
What should I avoid while taking memantine?
Can I drive while taking memantine?
How long will I need to take memantine?
What if I have kidney problems?
Can memantine cure Alzheimer's disease?
What happens if I stop taking memantine?
Are there any foods I should avoid?
Can I take memantine with other Alzheimer's medications?
What should I do if I think I'm experiencing a side effect?
Is there a generic version of memantine?
What are the common side effects of memantine?
Does memantine interact with other medications?
What drug class is memantine?
Is memantine safe during pregnancy?
Is memantine currently in shortage?
Related Medications in NMDA Receptor Antagonist
Other drugs grouped near memantine — same-class peers and common alternatives.
acamprosate
Campral
Acamprosate is a medicine that can help you stay away from alcohol if you are alcohol-dependent and have already stopped drinking.
Compare with memantine →
alprazolam
Xanax
Alprazolam (Xanax) is a medication that can help you with anxiety and panic disorders.
Compare with memantine →
amitriptyline
Elavil
Amitriptyline is a medicine used to treat depression.
Compare with memantine →
amphetamine/dextroamphetamine
Adderall, Adderall XR
Adderall XR is a stimulant medicine.
Compare with memantine →
aripiprazole
Abilify
Aripiprazole (Abilify) is a medicine used to treat certain mental disorders and mood problems.
Compare with memantine →
Medication Guides
Understanding Drug Interactions
How CYP450 enzymes, inhibitors, and inducers affect your medications
Generic vs Brand Name Drugs
FDA requirements, cost savings, and when the difference matters
Narrow Therapeutic Index Drugs
Why some drugs demand precise dosing and monitoring
Common Drug Interactions
Dangerous medication combinations and how to protect yourself
Related Health & Safety Data
🩺 Find a Doctor
Search prescribers for NMDA Receptor Antagonist
🏨 Hospital Quality
CMS hospital ratings, safety scores & patient outcomes
💊 Supplement Data
NIH DSLD — check supplement ingredients & label claims
🍽️ Food Safety Alerts
FDA recalls, inspections & outbreak investigations
⚠️ Product Recalls
FDA, CPSC & NHTSA recall search
💉 Procedure Costs
Medicare procedure pricing for 9,297 procedures
Save on memantine
Compare prices and find discounts at pharmacies near you. Free coupons can save up to 80% on prescriptions.
Disclosure: This link may earn us a commission at no extra cost to you. See our terms.
What the FDA Data Shows for memantine
The FDA label for memantine (sold under brand names such as Namenda) classifies it as a prescription-only medication in the NMDA Receptor Antagonist class. Memantine is used to treat moderate to severe Alzheimer's disease. Official labeling lists 4 commonly reported side effects, including Dizziness, Headache, Confusion.
Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 6,643 voluntary reports. The database also lists 2 documented drug interactions derived from FDA labeling, with the top-flagged interaction rated moderate severity. NADAC pricing from CMS shows a generic unit cost of $0.32.
Report counts do not establish causation — a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history, and patent information further shape supply and switching decisions. This page summarizes public FDA data for educational purposes only and is not a substitute for professional medical advice — always consult a licensed healthcare provider before starting, stopping, or changing any medication.
Data Sources
Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS). Pricing: CMS National Average Drug Acquisition Cost (NADAC). Shortage status: FDA Drug Shortages Database.
FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. Always consult a healthcare professional before making medication decisions.
Last updated: August 17, 2023
Read our methodology — how this data is sourced, computed, and verified.
All federal data sources used on this page
- FDA Orange Book — approved drug products with therapeutic equivalence. accessdata.fda.gov/cder/ob
- FDA DailyMed — NIH-hosted drug labeling for FDA-approved meds. dailymed.nlm.nih.gov
- FDA Adverse Event Reporting System (FAERS) — post-marketing safety surveillance. fda.gov/drugs/faers
- NLM RxNorm — standardized clinical drug nomenclature. nlm.nih.gov/research/umls/rxnorm
- CMS Medicare Part B Drug Average Sales Price Files — federal drug pricing data. cms.gov/medicare/part-b-drugs/asp
- FDA Drug Shortages Database — current and resolved drug shortage tracking. accessdata.fda.gov/drugshortages