Donepezil / Memantine Dosage

Medically reviewed by Drugs.com. Last updated on Oct 31, 2023.

Usual Adult Dose for Alzheimer's Disease

Patients stabilized on memantine (10 mg twice a day or 28 mg ER once a day) and donepezil 10 mg once a day:

• Memantine 28 mg ER-donepezil 10 mg orally once a day in the evening

Comments: This drug should be initiated the day following the last dose of memantine and donepezil administered separately.

Use:
Treatment of moderate to severe dementia of the Alzheimer's type in patients stabilized on

• Memantine (10 mg twice a day or 28 mg ER once a day) and donepezil 10 mg once a day, or
• Memantine (5 mg twice a day or 14 mg ER once a day) and donepezil 10 mg once a day in patients with severe renal impairment

Renal Dose Adjustments

• Mild to moderate renal dysfunction patients: No adjustment recommended
• Severe renal dysfunction (CrCl 5 to 29 mL/min) patients stabilized on memantine (5 mg twice a day or 14 mg ER once a day) and donepezil 10 mg once a day: Memantine 14 mg ER-donepezil 10 mg orally once a day in the evening

Liver Dose Adjustments

• Mild to moderate liver dysfunction: No adjustment recommended
• Severe liver dysfunction: Data not available

Precautions

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• This drug can be taken with or without food.
• This drug should be swallowed whole or the capsule may be opened, sprinkled on applesauce, and swallowed without chewing.
• Do not divide, chew, or crush the drug capsule.
• If a dose is missed, the next dose should be taken as scheduled without doubling up the dose.

Storage requirements: Keep this drug in a tight, light-resistant container.

Overdose:

• There is no specific antidote for memantine; however, elimination can be increased by acidification of the urine.
• Tertiary anticholinergics such as atropine may be used for donepezil overdose.

General:

• There is no evidence that memantine or donepezil prevent or slow neurodegeneration in patients with Alzheimer's disease.

Monitoring:

• Cardiovascular: Bradycardia, heart block, syncope
• Gastrointestinal: Nausea, vomiting, diarrhea (especially during therapy initiation); active or occult GI bleeding (particularly in patients with a history of ulcer disease or taking concurrent NSAIDs)
• Genitourinary: Bladder outflow obstruction
• Nervous system: Seizures, succinylcholine-type muscle relaxation during anesthesia
• Respiratory: Worsening of pulmonary diseases

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer