II. Indications: Moderate to Severe Dementia
- Consider as alternative to Cholinesterase Inhibitor (e.g. Aricept) if side effects limit use
- Memantine may be better tolerated than Cholinesterase Inhibitors
- Previously added on to Cholinesterase Inhibitor protocol for added benefit
- Combination therapy no longer recommended due to low efficacy (only helped 1 in 12)
- Combination therapy is associated with gastrointestinal side effects, Bradycardia and Syncope
III. Mechanism
- Amantadine derivative with Dopaminergic effects
- Non-Competitive Antagonist of Glutamate receptor (N-methyl-D-Aspartate)
IV. Dosing
- Background
- Memantine has a long enough half life to be dosed once daily
- Memantine regular once daily has equivalent efficacy to Mamantine XR
- Memantine regular is generic in 2015 (with brand name discontinued in 2014)
- Memantine (Namenda, Ebixa in Europe)
- Start: 5 mg orally orally daily for at least 1 week
- Next: 5 mg orally twice daily for at least 1 week
- Next: 10 mg orally each AM and 5 mg orally each night for at least 1 week
- Next: 10 mg orally twice daily
- Renal Dosing (GFR <30 ml/min): Maximum 5 mg/day
- Memantine ER (Namenda XR)
- Start 7 mg orally daily
- Titrate daily dose by 7 mg on a weekly basis to maximum of 28 mg daily
- Maximum 28 mg/day
- Renal Dosing (GFR <30 ml/min) Maximum 14 mg/day
V. Adverse Effects
- Common adverse effects
- Rare but serious adverse effects
VI. Efficacy
- Can improve cognition and function
VII. Pharmacokinetics
- Half-Life (Memantine): 60-80 hours
VIII. Resources
IX. References
- (2014) Presc Lett 21(5): 26
- (2013) Presc Lett 20(7): 41
- (2012) Presc Lett 19(5): 28
- Epperly (2017) Am Fam Physician 95(12): 771-8 [PubMed]
- Tariot (2004) JAMA 291:317-24 [PubMed]
- Howard (2012) N Engl J Med 366:893-903 [PubMed]
- Jaqua (2024) Am Fam Physician 110(3): 281-93 [PubMed]
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Related Studies
| memantine (on 12/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| MEMANTINE 5-10 MG TITRATION PK | Generic | $0.36 each |
| MEMANTINE HCL 10 MG TABLET | Generic | $0.08 each |
| MEMANTINE HCL 5 MG TABLET | Generic | $0.09 each |
| MEMANTINE HCL ER 14 MG CAPSULE | Generic | $0.63 each |
| MEMANTINE HCL ER 21 MG CAPSULE | Generic | $0.87 each |
| MEMANTINE HCL ER 28 MG CAPSULE | Generic | $0.60 each |
| MEMANTINE HCL ER 7 MG CAPSULE | Generic | $0.76 each |