dextromethorphan vs memantine
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Side-by-side comparison of dextromethorphan and memantine. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
moderate Known Drug Interaction
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.
Delsym, Robitussin
Namenda
Dextromethorphan is a medicine that helps to relieve coughs. It can also help with cold and flu symptoms.
Memantine is a medicine used to treat moderate to severe Alzheimer's disease. It may help with memory and thinking.
This medicine temporarily relieves symptoms from a cold. It can help with minor aches and pains, headache, and nasal and sinus congestion. It also helps with sore throat, cough due to minor throat and bronchial irritation, and reduces fever.
Memantine is used to treat moderate to severe Alzheimer's disease. Alzheimer's is a brain disease that slowly gets worse over time. Memantine may help improve memory, awareness, and the ability to perform daily tasks.
Dextromethorphan works by decreasing the activity in the part of your brain that causes you to cough. This helps to reduce your urge to cough. It does not treat the underlying cause of the cough.
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.
- • Dizziness
- • Nausea
- • Headache
- • Fatigue
- • Dizziness
- • Headache
- • Confusion
- • Constipation
- Drug Abuse 713
- Toxicity To Various Agents 678
- Overdose 594
- Dizziness 435
- Accidental Overdose 403
- Fall 937
- Death 853
- Confusional State 706
- Fatigue 605
- Hallucination 581
Do not use in children under 12 years of age.
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.
Talk to your doctor before taking this medicine if you are pregnant or breastfeeding. It is not known if this medicine will harm your unborn baby. It is also not known if this medicine passes into breast milk.
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.
How to Read This dextromethorphan vs memantine Comparison
dextromethorphan is classified in the Antitussive drug class, while memantine sits within the NMDA Receptor Antagonist class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are split between OTC and prescription status, which affects access and supervision.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, dextromethorphan has 2,823 submissions while memantine has 3,682. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known moderate interaction flagged in FDA labeling, attributed to 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.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for dextromethorphan or memantine.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.