--- title: "Memantine: Research & Side Effects | BodyHackGuide" url: https://www.bodyhackguide.co/compound/memantine description: "Memantine: mechanism, clinical studies & side effects." lang: en --- Skip to content Compare notes on r/BodyHackGuide (https://reddit.com/r/bodyhackguide) Compare notes with other researchers. Join r/BodyHackGuide (https://reddit.com/r/bodyhackguide) # Memantine Cognitive: https://www.bodyhackguide.co/wiki#cat-cognitive Status Approved (prescription) Evidence Not graded on a research bench yet Memantine (1-amino-3,5-dimethyladamantane) is a moderate-affinity, uncompetitive antagonist of the NMDA type of glutamate receptor that the FDA approved on 16 October 2003 as Namenda for moderate to severe dementia of the Alzheimer's type, under a US licence from the German company Merz. Reviewed 4 November 2026 01 Overview ## What Memantine is A 2019 Cochrane review of 44 trials found that memantine gives a small benefit over placebo in moderate to severe Alzheimer's disease, backed by high-certainty evidence, and probably no benefit in mild Alzheimer's disease (PMID: 30891742). The US label states that there is no evidence that memantine prevents or slows neurodegeneration in Alzheimer's disease (US prescribing information for memantine hydrochloride tablets). A 2010 systematic review found only seven small single-dose studies of memantine in healthy people and judged them inadequate to show cognitive enhancement (PMID: 20193764). ### How it works ### NMDA receptor channel block Memantine blocks the NMDA receptor (N-methyl-D-aspartate receptor), a glutamate-gated ion channel, as a moderate-affinity uncompetitive antagonist (PMID: 30891742). In whole-cell and single-channel recordings, a group led by Stuart Lipton showed in 1992 that memantine plugs the open receptor channel (open-channel block), as the research compound MK-801 does, but with faster blocking and unblocking, and that low micromolar memantine prevented NMDA receptor-mediated death of cultured rat cortical and retinal ganglion cell neurons (PMID: 1432103). The authors proposed that at these concentrations memantine should in theory allow near-normal NMDA receptor activity even when glutamate levels are pathologically high in one area (PMID: 1432103). A 2006 review by Lipton links memantine's approval to his group's discovery of its clinically tolerated mechanism (PMID: 16424917), and a review led by Chris Parsons of Merz describes memantine as a moderate-affinity uncompetitive antagonist with strong voltage dependence and fast kinetics and summarizes hypotheses for how this one action could both protect neurons from continuous low-level NMDA receptor overactivation and reverse learning deficits (PMID: 17904591). The US label calls memantine a low to moderate affinity uncompetitive (open-channel) NMDA receptor antagonist and states that there is no evidence that memantine prevents or slows neurodegeneration in patients with Alzheimer's disease (US prescribing information for memantine hydrochloride tablets). Read the full mechanism Show less ### Which NMDA receptors are blocked (cell studies) In rat hippocampal cultures, memantine at 1 to 10 micromolar blocked NMDA currents outside synapses (extrasynaptic receptors) with about twice the potency of the NMDA component of synaptic currents (PMID: 20720132). A University of Pittsburgh study found that magnesium at a physiological concentration reduced memantine's block of NR1/2A and NR1/2B receptors nearly 20-fold near resting membrane voltage, but reduced its block of NR1/2C and NR1/2D receptors only about 3-fold, and the authors suggested that the accepted explanations of how memantine works should be reconsidered (PMID: 19261873). ### Other receptors (cell studies) The US label reports that memantine blocks serotonin 5-HT3 receptors with a potency similar to its NMDA potency, blocks nicotinic acetylcholine receptors at one-sixth to one-tenth of that potency, and has low to negligible affinity for GABA, benzodiazepine, dopamine, adrenergic, histamine and glycine receptors (US prescribing information for memantine hydrochloride tablets). In HEK-293 and N1E-115 cells, memantine blocked 5-HT3 receptor currents with a potency similar to that reported for NMDA receptors (PMID: 11403963). A University of Maryland group reported a different result from the label's nicotinic figure in cultured rat hippocampal neurons: memantine blocked alpha7 nicotinic receptors more potently than NMDA receptors (IC50 0.34 against 5.1 micromolar), and the authors suggested that this block could reduce memantine's usefulness in Alzheimer's disease (PMID: 15522999). ### Pharmacokinetics in people According to the US label, memantine is highly absorbed by mouth with peak blood levels after about 3 to 7 hours, food does not change absorption, about 45 percent is bound to plasma proteins, and the cytochrome P450 system plays no significant role in its metabolism (US prescribing information for memantine hydrochloride tablets). About 48 percent of a dose is excreted unchanged in the urine, renal clearance involves active tubular secretion moderated by pH-dependent reabsorption, and the terminal elimination half-life is about 60 to 80 hours (US prescribing information for memantine hydrochloride tablets). Clearance fell by about 80 percent when urine was alkaline at pH 8 (US prescribing information for memantine hydrochloride tablets). In a single-dose study of 32 people with normal or reduced kidney function, memantine exposure (area under the curve) was 60 percent higher with moderate and 115 percent higher with severe kidney impairment than with normal function (PMID: 16413248). ### Studied for - Alzheimer's disease - Vascular dementia - Lewy body dementias - Glutamate and NMDA receptor pharmacology - Neuroprotection - Radiation-induced cognitive decline - Psychiatry - Cognitive enhancement in healthy people ### Benefits listed - Global, cognitive, daily-function and behavior ratings in moderate to severe Alzheimer's disease in a 2019 Cochrane review of placebo-controlled trials (PMID: 30891742) - Severe Impairment Battery and daily-function scores when added to donepezil in a 404-patient trial (PMID: 14734594) - Global impression and care dependence in a 166-patient nursing home trial in severe dementia (PMID: 10885864) - ADAS-cog cognitive scores in two 28-week vascular dementia trials (PMID: 12105362, PMID: 12409683) Show 3 more Show less - Global impression in dementia with Lewy bodies in a 199-patient trial (PMID: 20729148) - Time to cognitive decline during whole-brain radiotherapy in a 508-patient trial whose primary endpoint was not met (PMID: 23956241) - Working memory after 24 hours without sleep in a crossover study of 36 healthy volunteers (PMID: 32332458) 02 Research Free with email ## What the research shows No research bench grades Memantine yet. Benches compare compounds people pair, with the evidence for each. ### Unlock the research summary Enter your email to keep reading. It is free, and it opens these sections on every compound page in this browser. - A summary of the key research - Safety and side effects - A link to the PubMed results You also get the free peptide cheat sheet by email. Unsubscribe anytime. Have an account? Sign in (https://www.bodyhackguide.co/auth) 03 Safety ## Memantine side effects and interactions ### Side effects #### Common - Dizziness (7 percent against 5 percent on placebo in the label's pooled dementia trials) - Headache (6 against 3 percent in the same trials) - Confusion (6 against 5 percent) - Constipation (5 against 3 percent) #### Serious events - Slow heart rate in 18 French pharmacovigilance reports; all but one of the 7 cases with memantine as the only suspected drug resolved after memantine was stopped (PMID: 18500725) - Serious adverse events of the infections or infestations type, more frequent than with placebo in the TEAM-AD trial (PMID: 24381967) - Postmarketing reports of blood cell disorders, pancreatitis, hepatitis, acute renal failure, Stevens-Johnson syndrome and suicidal ideation, causality not established (US prescribing information) ### Who should not use it Contraindications The US label lists one contraindication for memantine: known hypersensitivity to memantine hydrochloride or to any excipient in the product (US prescribing information for memantine hydrochloride tablets). The cautions that follow come from the label and from published studies. Read all the contraindications and cautions Show less Memantine clearance fell by about 80 percent at urine pH 8, and the label advises caution with drugs such as carbonic anhydrase inhibitors and sodium bicarbonate and with conditions such as renal tubular acidosis or severe urinary tract infection that make urine alkaline (US prescribing information for memantine hydrochloride tablets). In a single-dose study, memantine exposure rose by 60 percent in moderate and 115 percent in severe kidney impairment (PMID: 16413248), and the label adjusts dosing in severe kidney impairment (US prescribing information for memantine hydrochloride tablets). Memantine has not been studied in severe liver impairment, and the label advises caution (US prescribing information for memantine hydrochloride tablets). In people with seizure disorders, memantine has not been systematically evaluated (US prescribing information for memantine hydrochloride tablets). Use with other NMDA receptor antagonists (amantadine, ketamine or dextromethorphan) has not been systematically evaluated, and the label advises caution (US prescribing information for memantine hydrochloride tablets). As for pregnancy and children, no adequate data exist in pregnant women, and safety and effectiveness in children have not been established (US prescribing information for memantine hydrochloride tablets). ### Interactions 4 pairings in our record: 2 with a caution and 2 to monitor. - Carbonic anhydrase inhibitors and sodium bicarbonate Caution Memantine clearance fell by about 80 percent at urine pH 8, so the label advises caution with drugs that make urine alkaline, such as carbonic anhydrase inhibitors and sodium bicarbonate (US prescribing information for memantine hydrochloride tablets). - Amantadine, ketamine and dextromethorphan Caution The label states that combined use of memantine with other NMDA receptor antagonists (amantadine, ketamine and dextromethorphan) has not been systematically evaluated and should be approached with caution (US prescribing information for memantine hydrochloride tablets). In 52 healthy adults, memantine combined with dextromethorphan plus quinidine showed no pharmacokinetic interaction for memantine or dextromethorphan, quinidine exposure rose by 25 percent, and adverse events were similar to either drug alone (PMID: 22712629). - Donepezil Monitor Memantine and donepezil did not change each other's pharmacokinetics, and the adverse event profile of the combination was similar to donepezil alone in a 24-week trial (US prescribing information for memantine hydrochloride tablets). In female rats the combination caused more neurodegeneration than memantine alone, a finding of unknown relevance to humans (US prescribing information for memantine hydrochloride tablets). - Drugs cleared by the kidney cationic transport system Monitor Memantine is partly cleared by tubular secretion through the kidney's cationic transport system, which hydrochlorothiazide, triamterene, metformin, cimetidine, ranitidine, quinidine and nicotine also use, so plasma levels of both drugs could change; in studies, memantine lowered hydrochlorothiazide bioavailability by 20 percent and did not interact with glyburide plus metformin (US prescribing information for memantine hydrochloride tablets). This interaction data is compiled from published research and community reports. It may not be exhaustive. Always consult a healthcare professional before combining compounds. Need bloodwork before starting? Full hormone + metabolic panels from Anabolic Insights. Code CHONCH for first-order discount. Order Bloodwork (https://anabolicinsights.ai/?ref=nwm2zjb) 04 Dosing Free with email ## Dosing No dose on record Our record lists no dose for Memantine. This section holds what it does list. ### Unlock the Dosing section - Route 05 Prices ## Memantine prices No listings We do not track a vendor for Memantine yet, so this page states no price. 06 Chemistry ## Chemistry and structure Molecular formula C12H21N Molecular mass 179.30 g/mol CAS number 19982-08-2 Half-life About 60 to 80 hours, the terminal elimination half-life given in the US prescribing information for memantine hydrochloride tablets, which also reports a half-life 95 percent longer in severe kidney impairment than in healthy subjects. View on PubChem (https://pubchem.ncbi.nlm.nih.gov/compound/4054) 07 Related ## Related to Memantine ### In the same category - FocusX BlendNo published studies of the blend FocusX Blend is a liquid sold for research in a 20 mL vial whose label lists three compounds at 150 mg/mL each: choline chloride, acetyl-L-carnitine and L-carnosine.: https://www.bodyhackguide.co/compound/focusx-blend - N-Acetyl-SelankPreclinical N-Acetyl-Selank is the N-terminally acetylated analog of Selank, a tuftsin-derived heptapeptide used intranasally for its reported anxiolytic and nootropic effects.: https://www.bodyhackguide.co/compound/n-acetyl-selank - N-Acetyl-SemaxDuplicate entry - see NA-Semax This is a duplicate/alias entry. The full, maintained guide for this compound lives at NA-Semax (/compound/na-semax).: https://www.bodyhackguide.co/compound/n-acetyl-semax - NicergolinePhase 3 Nicergoline (Sermion) is a semisynthetic ergot derivative that blocks alpha1-adrenergic receptors and has been in clinical use outside the US since the 1970s for cognitive, behavioral and cerebrovascular disorders of older people.: https://www.bodyhackguide.co/compound/nicergoline - Noopept + Choline Chloride BlendBlend has no clinical trials A community nootropic stack pairing Noopept, a potent racetam-family dipeptide, with a choline source (commonly alpha-GPC, CDP-choline/citicoline, or choline bitartrate).: https://www.bodyhackguide.co/compound/noopept-choline-blend All compounds (https://www.bodyhackguide.co/wiki) ### Compare Memantine - Alternatives to Memantine: https://www.bodyhackguide.co/alternatives-to/memantine ### Research tools - Peptide Calculator Reconstitution and syringe units: https://www.bodyhackguide.co/tools/reconstitution - Reconstitution Guide How to mix, step by step: https://www.bodyhackguide.co/guides/how-to-reconstitute-peptides - Nasal Spray Calc mL per actuation: https://www.bodyhackguide.co/tools/intranasal - Half-Life Visualizer Decay curves: https://www.bodyhackguide.co/tools/halflife All articles (https://www.bodyhackguide.co/blog) 08 Questions ## Frequently asked questions What is memantine? Memantine is an adamantane derivative, 1-amino-3,5-dimethyladamantane, that blocks the NMDA type of glutamate receptor as a moderate-affinity uncompetitive antagonist (PMID: 1432103, PMID: 30891742; US prescribing information for memantine hydrochloride tablets). Memantine was approved by the FDA in 2003 as Namenda for moderate to severe dementia of the Alzheimer's type, and the US product is licensed from the German company Merz (US prescribing information for memantine hydrochloride tablets; Drugs@FDA NDA 021487). Memantine has the formula C12H21N and a molecular weight of 179.30 g/mol in PubChem (CID 4054), and memantine hydrochloride, the salt used in tablets, weighs 215.76 g/mol (CID 181458). How well does memantine work in Alzheimer's disease? A 2019 Cochrane review found high-certainty evidence that memantine gives a small benefit over placebo in moderate to severe Alzheimer's disease, for example 3.11 points on the 100-point Severe Impairment Battery after six to seven months (PMID: 30891742, PMID: 14734594). In the DOMINO-AD trial, memantine's benefit on cognition and daily living over 52 weeks was smaller than the minimum differences the investigators considered clinically important (PMID: 22397651). The US label states that there is no evidence that memantine prevents or slows neurodegeneration in Alzheimer's disease (US prescribing information for memantine hydrochloride tablets). Does memantine help in mild Alzheimer's disease? The 2019 Cochrane review found that memantine probably makes no difference to cognition, daily living or behavior in mild Alzheimer's disease, and that memantine may increase stopping because of adverse events in that group (PMID: 30891742). In the TEAM-AD trial of 613 patients with mild to moderate Alzheimer's disease at Veterans Affairs medical centers, memantine did not significantly slow functional decline (PMID: 24381967). The Cochrane reviewers note that memantine is widely used off-label for mild Alzheimer's disease in the USA (PMID: 30891742). Has memantine been studied as a nootropic in healthy people? A 2010 systematic review found only seven small single-dose studies of memantine in healthy people and judged them inadequate to show cognitive enhancement (PMID: 20193764). In a 2020 crossover study of 36 healthy volunteers, 15 days of memantine lessened the drop in working memory accuracy after 24 hours without sleep compared with placebo (PMID: 32332458). An analysis of 136 online memantine reports found 42 describing nootropic use, and 77 of 100 chronic users in that analysis reported at least one side effect (PMID: 32602152). What are the side effects of memantine? In pooled dementia trials in the US label, the most common memantine side effects were dizziness (7 percent against 5 percent on placebo), headache (6 against 3 percent), confusion (6 against 5 percent) and constipation (5 against 3 percent) (US prescribing information for memantine hydrochloride tablets). The 2019 Cochrane review found no difference between memantine and placebo in the share of people with any adverse event (PMID: 30891742). Reports to the French pharmacovigilance database included 18 cases of slow heart rate with memantine; in 7 of them memantine was the only suspected drug, and all but one of these 7 cases resolved after memantine was stopped (PMID: 18500725). What interactions are listed for memantine? The memantine label advises caution with drugs and conditions that make urine alkaline, because memantine clearance fell by about 80 percent at urine pH 8 (US prescribing information for memantine hydrochloride tablets). The memantine label also advises caution when combining memantine with other NMDA receptor antagonists such as amantadine, ketamine or dextromethorphan, because the combinations have not been systematically evaluated (US prescribing information for memantine hydrochloride tablets). According to the label, memantine is not metabolized to a significant degree by cytochrome P450 enzymes (US prescribing information for memantine hydrochloride tablets). How long does memantine stay in the body? The US label gives memantine a terminal elimination half-life of about 60 to 80 hours, with about 48 percent of a dose excreted unchanged in urine (US prescribing information for memantine hydrochloride tablets). In a study of 32 people, memantine exposure was 60 percent higher with moderate and 115 percent higher with severe kidney impairment than with normal kidney function (PMID: 16413248). Related ## Articles on Memantine - Bromantane (Ladasten): What It Is and What the Research Shows Nootropics, 1 July 2026: https://www.bodyhackguide.co/blog/bromantane-research-guide Free 2026 Peptide Cheat Sheet (PDF) 38 compounds and blends: vial sizes, BAC water volumes, dosing ranges and bloodwork markers. Download Free (https://www.bodyhackguide.co/guides/peptide-cheat-sheet-download) BodyHackGuide (https://www.bodyhackguide.co/) Your biohacking research hub: compound pricing, brain health protocols, dosing tools, and vendor reviews. support@bodyhackguide.co Join our Discord: https://discord.gg/Mhq5UdRYBA r/BodyHackGuide on Reddit: https://reddit.com/r/BodyHackGuide **Affiliate Disclosure:** We rank every vendor on the same public, reproducible methodology (https://www.bodyhackguide.co/vendors/methodology). 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All rights reserved. - Terms: https://www.bodyhackguide.co/terms - Privacy: https://www.bodyhackguide.co/privacy ## Structured data ```json [ { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "Home", "item": "https://www.bodyhackguide.co/" }, { "@type": "ListItem", "position": 2, "name": "Compounds", "item": "https://www.bodyhackguide.co/compare" }, { "@type": "ListItem", "position": 3, "name": "Memantine" } ] }, { "@context": "https://schema.org", "@type": "MedicalWebPage", "name": "Memantine", "description": "Memantine (1-amino-3,5-dimethyladamantane) is a moderate-affinity, uncompetitive antagonist of the NMDA type of glutamate receptor that the FDA approved on 16 October 2003 as Namenda for moderate to severe dementia of the Alzheimer's type, under a US licence from the German company Merz (PMID: 30891742; Drugs@FDA NDA 021487; US prescribing information for memantine hydrochloride tablets). A 2019 Cochrane review of 44 trials found that memantine gives a small benefit over placebo in moderate to severe Alzheimer's disease, backed by high-certainty evidence, and probably no benefit in mild Alzheimer's disease (PMID: 30891742). The US label states that there is no evidence that memantine prevents or slows neurodegeneration in Alzheimer's disease (US prescribing information for memantine hydrochloride tablets). 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A 2019 Cochrane review of 44 trials found that memantine gives a small benefit over placebo in moderate to severe Alzheimer's disease, backed by high-certainty evidence, and probably no benefit in mild Alzheimer's disease (PMID: 30891742). The US label states that there is no evidence that memantine prevents or slows neurodegeneration in Alzheimer's disease (US prescribing information for memantine hydrochloride tablets). A 2010 systematic review found only seven small single-dose studies of memantine in healthy people and judged them inadequate to show cognitive enhancement (PMID: 20193764).", "activeIngredient": "Memantine", "administrationRoute": "Oral", "mechanismOfAction": "NMDA receptor channel block Memantine blocks the NMDA receptor (N-methyl-D-aspartate receptor), a glutamate-gated ion channel, as a moderate-affinity uncompetitive antagonist (PMID: 30891742). In whole-cell and single-channel recordings, a group led by Stuart Lipton showed in 1992 that memantine plugs the open receptor channel (open-channel block), as the research compound MK-801 does, but with faster blocking and unblocking, and that low micromolar memantine prevented NMDA receptor-mediated death of cultured rat cortical and retinal ganglion cell neurons (PMID: 1432103). The authors proposed that at these concentrations memantine should in theory allow near-normal NMDA receptor activity even when glutamate levels are pathologically high in one area (PMID: 1432103). A 2006 review by Lipton links memantine's approval to his group's discovery of its clinically tolerated mechanism (PMID: 16424917), and a review led by Chris Parsons of Merz describes memantine as a moderate-affinity uncompetitive antagonist with strong voltage dependence and fast kinetics and summarizes hypotheses for how this one action could both protect neurons from continuous low-level NMDA receptor overactivation and reverse learning deficits (PMID: 17904591). The US label calls memantine a low to moderate affinity uncompetitive (open-channel) NMDA receptor antagonist and states that there is no evidence that memantine prevents or slows neurodegeneration in patients with Alzheimer's disease (US prescribing information for memantine hydrochloride tablets). Which NMDA receptors are blocked (cell studies) In rat hippocampal cultures, memantine at 1 to 10 micromolar blocked NMDA currents outside synapses (extrasynaptic receptors) with about twice the potency of the NMDA component of synaptic currents (PMID: 20720132). A University of Pittsburgh study found that magnesium at a physiological concentration reduced memantine's block of NR1/2A and NR1/2B receptors nearly 20-fold near resting membrane voltage, but reduced its block of NR1/2C and NR1/2D receptors only about 3-fold, and the authors suggested that the accepted explanations of how memantine works should be reconsidered (PMID: 19261873). Other receptors (cell studies) The US label reports that memantine blocks serotonin 5-HT3 receptors with a potency similar to its NMDA potency, blocks nicotinic acetylcholine receptors at one-sixth to one-tenth of that potency, and has low to negligible affinity for GABA, benzodiazepine, dopamine, adrenergic, histamine and glycine receptors (US prescribing information for memantine hydrochloride tablets). In HEK-293 and N1E-115 cells, memantine blocked 5-HT3 receptor currents with a potency similar to that reported for NMDA receptors (PMID: 11403963). A University of Maryland group reported a different result from the label's nicotinic figure in cultured rat hippocampal neurons: memantine blocked alpha7 nicotinic receptors more potently than NMDA receptors (IC50 0.34 against 5.1 micromolar), and the authors suggested that this block could reduce memantine's usefulness in Alzheimer's disease (PMID: 15522999). Pharmacokinetics in people According to the US label, memantine is highly absorbed by mouth with peak blood levels after about 3 to 7 hours, food does not change absorption, about 45 percent is bound to plasma proteins, and the cytochrome P450 system plays no significant role in its metabolism (US prescribing information for memantine hydrochloride tablets). About 48 percent of a dose is excreted unchanged in the urine, renal clearance involves active tubular secretion moderated by pH-dependent reabsorption, and the terminal elimination half-life is about 60 to 80 hours (US prescribing information for memantine hydrochloride tablets). Clearance fell by about 80 percent when urine was alkaline at pH 8 (US prescribing information for memantine hydrochloride tablets). In a single-dose study of 32 people with normal or reduced kidney function, memantine exposure (area under the curve) was 60 percent higher with moderate and 115 percent higher with severe kidney impairment than with normal function (PMID: 16413248).", "legalStatus": "Approved (prescription)" } }, { "@context": "https://schema.org", "@type": "FAQPage", "mainEntity": [ { "@type": "Question", "name": "What is memantine?", "acceptedAnswer": { "@type": "Answer", "text": "Memantine is an adamantane derivative, 1-amino-3,5-dimethyladamantane, that blocks the NMDA type of glutamate receptor as a moderate-affinity uncompetitive antagonist (PMID: 1432103, PMID: 30891742; US prescribing information for memantine hydrochloride tablets). Memantine was approved by the FDA in 2003 as Namenda for moderate to severe dementia of the Alzheimer's type, and the US product is licensed from the German company Merz (US prescribing information for memantine hydrochloride tablets; Drugs@FDA NDA 021487). Memantine has the formula C12H21N and a molecular weight of 179.30 g/mol in PubChem (CID 4054), and memantine hydrochloride, the salt used in tablets, weighs 215.76 g/mol (CID 181458)." } }, { "@type": "Question", "name": "How well does memantine work in Alzheimer's disease?", "acceptedAnswer": { "@type": "Answer", "text": "A 2019 Cochrane review found high-certainty evidence that memantine gives a small benefit over placebo in moderate to severe Alzheimer's disease, for example 3.11 points on the 100-point Severe Impairment Battery after six to seven months (PMID: 30891742, PMID: 14734594). In the DOMINO-AD trial, memantine's benefit on cognition and daily living over 52 weeks was smaller than the minimum differences the investigators considered clinically important (PMID: 22397651). The US label states that there is no evidence that memantine prevents or slows neurodegeneration in Alzheimer's disease (US prescribing information for memantine hydrochloride tablets)." } }, { "@type": "Question", "name": "Does memantine help in mild Alzheimer's disease?", "acceptedAnswer": { "@type": "Answer", "text": "The 2019 Cochrane review found that memantine probably makes no difference to cognition, daily living or behavior in mild Alzheimer's disease, and that memantine may increase stopping because of adverse events in that group (PMID: 30891742). In the TEAM-AD trial of 613 patients with mild to moderate Alzheimer's disease at Veterans Affairs medical centers, memantine did not significantly slow functional decline (PMID: 24381967). The Cochrane reviewers note that memantine is widely used off-label for mild Alzheimer's disease in the USA (PMID: 30891742)." } }, { "@type": "Question", "name": "Has memantine been studied as a nootropic in healthy people?", "acceptedAnswer": { "@type": "Answer", "text": "A 2010 systematic review found only seven small single-dose studies of memantine in healthy people and judged them inadequate to show cognitive enhancement (PMID: 20193764). In a 2020 crossover study of 36 healthy volunteers, 15 days of memantine lessened the drop in working memory accuracy after 24 hours without sleep compared with placebo (PMID: 32332458). An analysis of 136 online memantine reports found 42 describing nootropic use, and 77 of 100 chronic users in that analysis reported at least one side effect (PMID: 32602152)." } }, { "@type": "Question", "name": "What are the side effects of memantine?", "acceptedAnswer": { "@type": "Answer", "text": "In pooled dementia trials in the US label, the most common memantine side effects were dizziness (7 percent against 5 percent on placebo), headache (6 against 3 percent), confusion (6 against 5 percent) and constipation (5 against 3 percent) (US prescribing information for memantine hydrochloride tablets). The 2019 Cochrane review found no difference between memantine and placebo in the share of people with any adverse event (PMID: 30891742). Reports to the French pharmacovigilance database included 18 cases of slow heart rate with memantine; in 7 of them memantine was the only suspected drug, and all but one of these 7 cases resolved after memantine was stopped (PMID: 18500725)." } }, { "@type": "Question", "name": "What interactions are listed for memantine?", "acceptedAnswer": { "@type": "Answer", "text": "The memantine label advises caution with drugs and conditions that make urine alkaline, because memantine clearance fell by about 80 percent at urine pH 8 (US prescribing information for memantine hydrochloride tablets). The memantine label also advises caution when combining memantine with other NMDA receptor antagonists such as amantadine, ketamine or dextromethorphan, because the combinations have not been systematically evaluated (US prescribing information for memantine hydrochloride tablets). According to the label, memantine is not metabolized to a significant degree by cytochrome P450 enzymes (US prescribing information for memantine hydrochloride tablets)." } }, { "@type": "Question", "name": "How long does memantine stay in the body?", "acceptedAnswer": { "@type": "Answer", "text": "The US label gives memantine a terminal elimination half-life of about 60 to 80 hours, with about 48 percent of a dose excreted unchanged in urine (US prescribing information for memantine hydrochloride tablets). In a study of 32 people, memantine exposure was 60 percent higher with moderate and 115 percent higher with severe kidney impairment than with normal kidney function (PMID: 16413248)." } } ] }, { "@context": "https://schema.org", "@type": "Organization", "@id": "https://www.bodyhackguide.co#organization", "name": "BodyHackGuide", "alternateName": "BHG", "url": "https://www.bodyhackguide.co", "logo": { "@type": "ImageObject", "url": "https://www.bodyhackguide.co/logo.png", "width": 512, "height": 512 }, "description": "Evidence-based research reference for peptides and nootropics. 273 compound profiles, interactive dosing calculators, vendor price comparisons, and trust-scored vendor reviews scored on a public, reproducible methodology applied to every vendor. 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