OpenClaim

Memantine Side Effects

The most commonly reported side effects of memantine include death, fall, and off label use, based on 27,915 FDA adverse event reports from 2004 to 2025. 4.7% of reports found the drug to be ineffective.

Memantine side effects

Percentages show how often each reaction appears relative to total reports for memantine.

1
Death5.5%1,525
2
Fall5.4%1,512
3
Drug Ineffective4.7%1,317
4
Off Label Use4.4%1,217
5
Confusional State4.0%1,103
6
Fatigue3.7%1,038
7
Hallucination3.3%922
8
Dizziness3.0%840
9
Confusional State2.9%820
10
Asthenia2.8%778
11
Diarrhoea2.6%719
12
Nausea2.4%683
13
Condition Aggravated2.4%678
14
Somnolence2.4%658
15
Urinary Tract Infection2.3%650

These are voluntary reports and do not establish that memantine caused these reactions.

Report severity

68.2%Serious19,032 reports
34.8%Hospitalizations9,704 reports
13.8%Fatal3,855 reports

Seriousness is determined by the reporter, not by OpenClaim.

Memantine drug interactions

Other drugs that appear in adverse event reports alongside memantine. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Pimavanserin7.7%2,156
2
Donepezil-hydrochloride5.3%1,481
3
Rivastigmine3.1%853
4
Quetiapine-fumarate2.9%803
5
Levodopa2.7%764
6
Carbidopa2.3%656
7
Lenalidomide2.1%600
8
Risperidone1.7%483
9
Sodium-oxybate1.2%335
10
Olanzapine1.2%331
11
Aspirin1.2%328
12
Pregabalin1.2%322
13
Apixaban1.1%309
14
Sertraline-hydrochloride1.1%299
15
Rivaroxaban1.0%290

Taken alongside

1
Donepezil-hydrochloride22.5%6,280
2
Aspirin16.6%4,621
3
Levothyroxine-sodium11.7%3,271
4
Atorvastatin-calcium11.6%3,247
5
Ergocalciferol10.8%3,023
6
Acetaminophen10.2%2,844
7
Amlodipine9.0%2,502
8
Omeprazole8.6%2,404
9
Carbidopa8.2%2,299
10
Metoprolol8.1%2,257
11
Furosemide7.9%2,219
12
Levodopa7.5%2,105
13
Quetiapine-fumarate7.1%1,984
14
Gabapentin6.9%1,940
15
Simvastatin6.9%1,927

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports memantine side effects

50.5% of memantine adverse event reports involve female patients and 41.7% involve male patients. The largest age group is elderly at 83%. These figures reflect who reports side effects, not underlying risk.

Sex

Female50.5%
Male41.7%
Unknown7.8%

Age group

< 20.1%
2–110.5%
12–170.4%
18–6416.1%
65+82.9%

What is memantine used for

Conditions and purposes for which patients were taking memantine when the adverse event was reported.

Abnormal BehaviourAccidental Exposure To ProductAccidental Exposure To Product By ChildAccidental OverdoseAffective DisorderAggressionAgitationAlcohol Induced Persisting DementiaAltered State Of ConsciousnessAltered Visual Depth PerceptionAlzheimer^s DiseaseAmnesiaAmyloidosisAnterograde AmnesiaAnticoagulant Therapy

Showing 15 of 475 indications

Memantine brand names and reporting trend

Memantine is sold under the brand name Memantine Hydrochloride And Donepezil Hydrochloride.

Brand names

Memantine Hydrochloride And Donepezil Hydrochloride192

Quarterly reports (20042025)

20052010201520202025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking memantine with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.