donepezil hydrochloride

(doe nep' ah zill)

Aricept

 

Pregnancy Category C

 

Drug classes

Cholinesterase inhibitor

Alzheimer's disease drug

 

Therapeutic actions

Centrally acting reversible cholinesterase inhibitor leading to elevated acetylcholine levels in the cortex, which slows the neuronal degradation that occurs in Alzheimer's disease.

 

Indications

        Treatment of mild to moderate dementia of the Alzheimer's type

 

Contraindications and cautions

        Contraindicated with allergy to donepezil.

        Use cautiously with sick sinus syndrome, GI bleeding, seizures, asthma, pregnancy, lactation.

 

Available forms

Tablets—5, 10 mg

 

Dosages

ADULTS

5 mg PO daily hs. May be increased to 10 mg daily after 4–6 wk.

PEDIATRIC PATIENTS

Safety and efficacy not established.

 

Pharmacokinetics

Route

Onset

Peak

Oral

Varies

2–4 hr

Metabolism: Hepatic; T1/2: 70 hr

Distribution: Crosses placenta; may enter breast milk

Excretion: Urine

 

Adverse effects

        CNS: Insomnia, fatigue, dizziness, confusion, ataxia, somnolence, tremor, agitation, depression, anxiety, abnormal thinking

        Dermatologic: Rash, flushing, purpura

        GI: Nausea, vomiting, diarrhea, dyspepsia, anorexia, abdominal pain, flatulence, constipation, hepatotoxicity

        Other: Muscle cramps

 

Interactions

        Increased effects and risk of toxicity with theophylline, cholinesterase inhibitors

        Decreased effects of anticholinergics

        Increased risk of GI bleeding with NSAIDs

        Decreased efficacy with anticholinergics

 

Nursing considerations

CLINICAL ALERT!

 

Assessment

        History: Allergy to donepezil, pregnancy, lactation, sick sinus syndrome, GI bleeding, seizures, asthma

        Physical: Orientation, affect, reflexes; BP, P; abdominal examination; renal and liver function tests

 

Interventions

        Administer hs each day.

        Provide small, frequent meals if GI upset is severe.

        Notify surgeons that patient is on donepezil; exaggerated muscle relaxation may occur if succinylcholine-type drugs are used.

 

Teaching points

        Take this drug exactly as prescribed, at bedtime.

        This drug does not cure the disease but is thought to slow down the degeneration associated with the disease.

        Arrange for regular blood tests and follow-up visits while adjusting to this drug.

        You may experience these side effects: Nausea, vomiting (eat frequent small meals); insomnia, fatigue, confusion (use caution if driving or performing tasks that require alertness).

        Report severe nausea, vomiting, changes in stool or urine color, diarrhea, changes in neurologic functioning, yellowing of eyes or skin.

 

Adverse effects in Italic are most common; those in Bold are life-threatening.