What is the recommended dose of Aricept (donepezil) for patients with dementia?

Aricept Dosing for Dementia

Start donepezil at 5 mg once daily in the evening just prior to retiring, then increase to 10 mg daily after 4-6 weeks if well tolerated. 1, 2

Initial Dosing for Mild to Moderate Alzheimer's Disease

• Begin with 5 mg once daily in the evening, just before bedtime 1, 2
• Take with or without food 2
• Escalate to 10 mg once daily after 4-6 weeks if the patient tolerates the initial dose 1, 2
• The 10 mg dose provides superior cognitive and functional benefits compared to 5 mg 3

Dosing for Moderate to Severe Alzheimer's Disease

• Start with the same 5 mg daily dose in the evening 2
• Increase to 10 mg daily after 4-6 weeks 2
• A 23 mg daily dose is FDA-approved for moderate to severe disease, but should only be administered after patients have been on 10 mg daily for at least 3 months 2
• The 23 mg tablet must not be split, crushed, or chewed 2

Dosing for Vascular Dementia

• Use the same dosing schedule as Alzheimer's disease: 5 mg daily initially, then 10 mg daily after 4-6 weeks 3, 4
• Evidence supports benefit in vascular dementia, though effects are smaller than in Alzheimer's disease 5, 4

Critical Timing and Administration Details

• Always administer in the evening just prior to retiring to minimize sleep disturbances 1, 2
• The gradual 4-6 week titration period is essential to minimize gastrointestinal side effects 1, 6
• Donepezil has a 70-hour half-life, making once-daily dosing appropriate 7, 8

Expected Clinical Effects

• Donepezil produces statistically significant improvements in cognition (ADAS-cog) and global function (CIBIC-plus), but does not achieve the 4-point change in ADAS-cog considered clinically significant 3, 5
• Benefits on cognitive function, activities of daily living, and behavior are maintained for approximately 21-81 weeks with 10 mg daily 5, 9
• A subset of patients will achieve clinically meaningful improvement even though average improvements are modest 3

Side Effect Management

• Gastrointestinal effects are dose-dependent: nausea/vomiting (relative risk 2.54), diarrhea (relative risk 2.57), and anorexia (relative risk 3.21) are significantly more common at 10 mg versus 5 mg 1, 6
• Taking donepezil with food and using gradual titration minimizes these effects 1
• Initial agitation typically subsides after the first few weeks 5, 6
• Monitor for bradycardia and cardiovascular effects, particularly in patients with underlying cardiac conduction abnormalities 6, 2
• No hepatotoxicity occurs with donepezil, unlike tacrine, so liver function monitoring is not required 6, 9

Common Pitfalls to Avoid

• Do not prescribe donepezil for mild cognitive impairment—evidence shows no significant benefit in this population 3, 5
• Do not start at 10 mg daily; always begin with 5 mg to improve tolerability 1, 2
• Do not administer in the morning, as this increases sleep disturbances 1
• Do not expect dramatic clinical improvement; effects are statistically significant but modest in magnitude 5
• Withdrawal rates due to adverse events ranged from 0-57% in treatment groups, emphasizing the importance of proper titration 3, 6

Evidence Quality

The American College of Physicians and American Academy of Family Physicians guidelines are based on high-quality evidence from 24 studies evaluating donepezil in Alzheimer's disease and vascular dementia 3. The FDA labeling provides definitive dosing instructions 2. The strength of evidence for donepezil's efficacy in mild to moderate Alzheimer's disease is high, with multiple well-designed trials demonstrating consistent benefits 3, 5.