Memantine

Brand Name: Namenda XR, Namenda

Generic Name: memantine

Drug Class: NMDA Antagonists

What Is Memantine and How Does It Work?

Memantine is a prescription drug used to treat moderate to severe confusion (dementia) related to Alzheimer's disease. It does not cure Alzheimer's disease, but it may improve memory, awareness, and the ability to perform daily functions. This medication works by blocking the action of a certain natural substance in the brain (glutamate) that is believed to be linked to symptoms of Alzheimer's disease.

Memantine is available under the following different brand names: Namenda XR, and Namenda.

Dosages of Memantine:

Tablet

• 5 mg
• 10 mg

Capsule, extended-release

• 7 mg
• 14 mg
• 21 mg
• 28 mg

Oral solution

• 2 mg/ml

Not indicated for pediatric use

Dosage Considerations – Should be Given as Follows:

Alzheimer-Type Dementia

• Treatment of moderate-to-severe dementia
• Tablet: 5 mg orally once daily initially; increased by increments of 5 mg/day each week; maintenance target dosage (more than 5 weeks): 20 mg/day orally divided every 12 hours
• Extended-release capsule: 7 mg orally each day initially; may be increased by increments of 7 mg/day each week; maintenance target dose is 28 mg orally each day

Dosage Modifications

Renal impairment

• Mild or moderate: No dosage adjustment required
• Severe: (creatinine clearance of 5-29 mL/min): Not to exceed 14 mg/day (extended-release) or 5 mg twice daily (prompt-release)

Hepatic impairment

• Mild or moderate (Child Pugh A/B): No dosage adjustment required
• Severe (Child Pugh C): Caution

Administration

• May take with or without food
• Consume entire capsule contents, do not divide the dose
• Swallow capsule whole or open and sprinkle on spoonful of applesauce; do not chew or crush
• Do not mix oral solution with any other liquid
• Missed dose: Do not double next dose, the next dose should be taken as scheduled; if missed for several days, dosing may need to be resumed at lower doses and re-titrated as described above

Mild-to-Moderate Vascular Dementia (off-label)

• 5 mg (immediate-release) orally daily; titrate by 5 mg every 7 days to target dose 10 mg twice daily