What is the recommended initial dose of dementia medication like donepezil for an elderly patient?

Recommended Initial Dose of Donepezil for Elderly Patients with Dementia

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

Initial Dosing Protocol

• The FDA-approved starting dose is 5 mg once daily for all patients with mild to moderate Alzheimer's disease, regardless of age 2
• Take the medication in the evening before bedtime 1, 2
• Can be taken with or without food, though taking with food may reduce gastrointestinal side effects 1

Dose Escalation Timeline

• Wait a minimum of 4 to 6 weeks at the 5 mg dose before considering escalation to 10 mg daily 1, 2
• This waiting period allows assessment of tolerability and initial response 1
• For moderate to severe dementia, if further escalation is needed, wait at least 3 months on the 10 mg dose before considering 23 mg daily 2

Assessment Period for Benefit

• Allow 6 to 12 months of treatment to adequately assess potential benefit 1, 3
• Beneficial effects are generally observed within 3 months, but full assessment requires longer observation 3
• Use comprehensive assessments including caregiver reports and functional measures, as brief mental status tests are relatively insensitive to cholinesterase inhibitor effects 3

Managing Side Effects

• Most common adverse effects are nausea, vomiting, and diarrhea, which occur more frequently at 10 mg than 5 mg 1, 2
• These gastrointestinal effects can be minimized by taking donepezil with food and using gradual dose titration 3
• Initial increase in agitation may occur in some patients but typically subsides after a few weeks 1
• If side effects develop and do not resolve, discontinue the medication 1

Common Pitfalls to Avoid

• Do not start at 10 mg daily - this increases the risk of intolerable side effects and early discontinuation 1, 2
• Avoid premature discontinuation - some patients require up to 12 months to demonstrate benefit 3
• Do not split, crush, or chew the 23 mg tablet if that dose is eventually prescribed 2
• Address unrealistic expectations before initiating treatment - the goal is slowing decline, not reversal 3

When to Consider Discontinuation

Discontinue donepezil if: 1

• Side effects develop and do not resolve
• Adherence is poor
• Deterioration continues at the pretreatment rate after 6 to 12 months of treatment
• The patient develops severe or end-stage dementia with dependence in most basic activities of daily living 1

Alternative Strategies

• Patients who do not respond to one cholinesterase inhibitor may respond to another 1
• For patients continuing to decline on donepezil monotherapy after adequate trial, consider adding memantine while continuing donepezil 3