donepezil (doe-nep-i-zill) Aricept, Aricept ODT

 Indications

Mild, moderate, or severe dementia/neurocognitive disorder

associated with Alzheimer’s disease.

Action

Inhibits acetylcholinesterase thus improving cholinergic

function by making more acetylcholine available.

Therapeutic Effects: May temporarily lessen some

of the dementia associated with Alzheimer’s disease.

Enhances cognition. Does not cure the disease.

Pharmacokinetics

Absorption: Well absorbed after oral administration.

Distribution: Unknown.

Protein Binding: 96%.

Metabolism and Excretion: Partially metabolized

by the liver (CYP2D6 and CYP3A4 enyzmes) and partially

excreted by kidneys (17% unchanged). Two metabolites

are pharmacologically active.

Half-life: 70 hr.

TIME/ACTION PROFILE (improvement in

symptoms)

ROUTE ONSET PEAK DURATION

PO unknown several wk 6 wk†

†Return to baseline after discontinuation.

Contraindications/Precautions

Contraindicated in: Hypersensitivity to donepezil

or piperidine derivatives. 

Use Cautiously in: Underlying cardiac disease, especially

sick sinus syndrome or supraventricular conduction

defects; History of ulcer disease or currently

taking NSAIDs; History of seizures; History of asthma or

obstructive pulmonary disease; OB, Lactation, Pedi:

Safety not established; assumed to be secreted in breast

milk. Discontinue drug or bottle-feed.

Adverse Reactions/Side Effects

CNS: headache, abnormal dreams, depression, dizziness,

drowsiness, fatigue, insomnia, syncope, sedation

(unusual). CV: atrial fibrillation, hypertension, hypotension,

vasodilation. GI: diarrhea, nausea, anorexia,

vomiting, weight gain (unusual). GU: frequent urination.

Derm: ecchymoses.Metab: hot flashes, weight

loss. MS: arthritis, muscle cramps.

Interactions

Drug-Drug: Exaggerates muscle relaxation from

succinylcholine. Interferes with the action of anticholinergics.

qcholinergic effects of bethanechol.

Mayqrisk of GI bleeding from NSAIDs. Quinidine

and ketoconazolepmetabolism of donepezil. Rifampin,

carbamazepine, dexamethasone, phenobarbital,

and phenytoin induce the enzymes that metabolize

donepezil and maypits effects.

Drug-Natural Products: Jimson weed and scopolia

may antagonize cholinergic effects.

Route/Dosage

Mild to Moderate Alzheimer’s Disease

PO (Adults): 5 mg once daily; after 4–6 wk mayqto

10 mg once daily (dose should not exceed 5 mg/day in

frail, elderly females).

Severe Alzheimer’s Disease

PO (Adults): 5 mg once daily; mayqto 10 mg once

daily after 4–6 wk; after 3 mo, may thenqto 23 mg

once daily.

Availability (generic available)

Tablets: 5 mg, 10 mg, 23 mg. Cost: Aricept—23 mg

$1,059.91/90; Generic—All strengths $23.97/90.

Orally disintegrating tablets: 5 mg, 10 mg. Cost:

Generic—All strengths $233.62/30. In combination

with: memantine (Namzaric). See Appendix B.