Drugs › N-methyl-D-aspartate receptor antagonist
Generic name
Memantine hcl: adverse event reports filed with FDA
1,070 reports list it as a suspect or interacting product, 2004–2025. Class: N-methyl-D-aspartate receptor antagonist.
- 1,070
- reports as suspect product
- 0% of all reports · about 48 a year
- 0
- reports, 12 months to June 2026
- 2 in the 12 months before
- 95.3%
- marked serious by the reporter
- 92.6% across the class
- 17.4%
- record death among outcomes, as reported
- 186 reports · not verified by FDA
Between January 2004 and June 2025, 1,070 adverse event reports received by FDA list memantine hcl, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (838) are left out of every figure here.
In the 12 months to June 2026, 0 reports listed it, against 2 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 48 reports a year and 0% of the 20,646,523 reports in the database, and 18.2% of the reports for the n-methyl-D-aspartate receptor antagonist class. How many people take it is not in the data, so a count is not a rate of occurrence.
The MedDRA terms listed most often are fall (9%), confusional state (6.1%) and agitation (5.8%). A report can list several reactions, so shares add to more than 100%; 411 different terms appear across these reports. Fall is recorded in 9% of these reports, a larger share than in the median n-methyl-D-aspartate receptor antagonist drug (7.2%).
95.3% of the reports are marked serious by the reporter (92.6% across the class); 17.4% record death among the outcomes and 53.6% record hospitalisation, as reported. 49.2% of the reports came from other health professionals, and the largest patient age group is 75 and over (54.1%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."
Reports by month, five years
Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.
By year received
Reactions recorded in the reports
share of Memantine hcl reports recording the termmedian drug in n-methyl-d-aspartate receptor antagonist
- Falla fall9%96
- Confusional stateconfusion6.1%65
- Agitationrestlessness5.8%62
- Condition aggravatedthe condition being treated got worse5.7%61
- Drug interactionan interaction between medicines5.7%61
- Somnolencedrowsiness5.3%57
- Aggressionaggressive behaviour4.7%50
- Dizzinesslight-headedness or unsteadiness4.7%50
- Abnormal behaviourunusual behaviour4.1%44
- General physical health deteriorationgeneral decline in health4.1%44
- Convulsion3.8%41
- Dehydrationdehydration3.8%41
- Malaisegeneral feeling of being unwell3.8%41
- Astheniaweakness or lack of energy3.7%40
- Loss of consciousnesspassing out3.3%35
- Nauseafeeling sick3.3%35
- Blood glucose increasedraised blood sugar reading3%32
- Gait disturbancedifficulty walking3%32
- Disorientation2.9%31
- Tremorshaking2.9%31
- Hallucinationseeing or hearing things that are not there2.7%29
- Urinary tract infectionbladder or urinary infection2.7%29
- Vomitingbeing sick2.7%29
- Pyrexiafever2.6%28
- Fatiguetiredness2.5%27
- Deaththe patient died; cause not stated by this term2.4%26
- Hypotensionlow blood pressure2.4%26
- Epilepsy2.3%25
- Blood urea increased2.2%24
- Restlessnessrestlessness2.2%24
Top 30 of 411 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 3 drugs in the n-methyl-d-aspartate receptor antagonist class; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."
Outcomes recorded
Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 5,879 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."
Patients and reporters
Patient age
Patient sex
Who reported
Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 18.6% of reports give the United States as the country of the event or reporter.
Reason for use recorded
| Indication as recorded (MedDRA) | Reports | Share |
|---|---|---|
| Dementia alzheimer's type | 506 | 47.3% |
| Dementia | 102 | 9.5% |
| Abnormal behaviour | 8 | 0.7% |
| Cognitive disorder | 6 | 0.6% |
| Open angle glaucoma | 5 | 0.5% |
| Ill-defined disorder | 3 | 0.3% |
The indication field is filled in by the reporter and is often blank; shares are of all 1,070 reports.
In context
| Measure | Memantine hcl | N-methyl-D-aspartate receptor antagonist | All reports |
|---|---|---|---|
| Reports as suspect product | 1,070 | 5,879 | 20,646,523 |
| Share of that pool | — | 18.2% | 0% |
| Reports, latest 12 months | 0 | — | 1,332,454 |
| Marked serious | 95.3% | 92.6% | 57.4% |
| Death recorded among outcomes, per 1,000 reports | 174 | 128 | 91 |
| Hospitalisation recorded, per 1,000 reports | 536 | 485 | 213 |
| Consumer-filed share | 8.3% | 13.4% | 45.8% |
| Top term, share of reports | Fall 9% | median 7.2% | 1.6% |
Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."
Other drugs in the n-methyl-d-aspartate receptor antagonist class
| Drug | Name type | Reports | Latest 12 months | Marked serious |
|---|---|---|---|---|
| Memantine | generic | 3,485 | 246 | 92.4% |
| Memantine hydrochloride | generic | 1,324 | 53 | 91% |
Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." A brand and its generic are separate rows because reporters name them separately.
Questions about Memantine hcl reports
How many adverse event reports has FDA received for Memantine hcl?
1,070 reports list Memantine hcl as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 0 of them arrived in the latest 12 months. Another 838 list it only as a concomitant medication.
What reactions are recorded in Memantine hcl reports?
fall (9%), confusional state (6.1%), agitation (5.8%), condition aggravated (5.7%) and drug interaction (5.7%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Memantine hcl was responsible.
How serious are the reports?
95.3% are marked serious by the reporter. Among the outcomes recorded, 17.4% of reports include death and 53.6% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.
Who files these reports?
other health professional (49.2%), not given (22.6%) and physician (10.7%). Most reports reach FDA through the manufacturer, which must forward reports it receives.
Are reports for Memantine hcl rising?
0 reports in the 12 months to June 2026, against 2 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.
Do these reports show that Memantine hcl was responsible for these reactions?
No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.
Is this a list of the side effects of Memantine hcl?
No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.
How do I report an adverse event?
Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.
Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Memantine hcl as a suspect or interacting product; reports listing it only as a concomitant medication (838) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.
Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.