DONEPEZIL (ARICEPT).MODE OF ACTION Reversible Cholinesterase Inhibitor Preferential inhibition of acetyicholinesterase in the central nervous system. Increases concentration of acetylcholine by preventing its hydrolysis by cholinesterase. Result is improved cholinergic transmission of nerve impulses. EFFECTS ON ALZHEIMER'S DISEASE Used to treat mild to moderate Alzheimer's disease. Benefits of therapy are modest and transient. Improvement in or stabilization of cognitive functioning may be seen in up to 89% of patients. CONTRAINDICATIONS Known hypersensitivity to donepezil or piperidine pi·per·i·dine n. A strongly basic, colorless liquid from which certain phenothiazine antipsychotics are derived. derivatives. Pregnancy Category C Pregnancy category C No adequate human or animal studies; or adverse fetal effects in animal studies, but no available human data. Mentioned in: Antianxiety Drugs . ADVERSE EFFECTS Gastrointestinal adverse effects, such as nausea (11%), vomiting (5%), anorexia (4%), and weight loss (3%). Central nervous system effects include insomnia (9%), dizziness (8%), depression (3%), abnormal dreams (3%), somnolence (2%), and headache (10%). Other observed adverse effects include muscle cramps (6%), dermatological effects (1%), fatigue (5%), urinary symptoms(2%), and arthritis (1%). DRUG-DRUG INTERACTIONS Inducers of cytochrome P450 2D6 and 3A4, such as carbamazepine carbamazepine /car·ba·maz·e·pine/ (kahr?bah-maz´e-pen) an anticonvulsant and analgesic used in the treatment of pain associated with trigeminal neuralgia and in epilepsy manifested by certain types of seizures. (Tegretol), dexamethasone, ketoconazole (Nizoral), pheno barbital bar·bi·tal n. A white crystalline barbiturate used as a sedative and hypnotic, especially in the form of its soluble salt, sodium barbital. barbital, barbitone a long-acting barbiturate, used as a hypnotic and sedative. , phenytoin phenytoin /phen·y·to·in/ (fen´i-toin?) an anticonvulsant used in the control of various kinds of epilepsy and of seizures associated with neurosurgery. phen·y·to·in n. (Dilantin), quinidine quinidine (kwĭn`ĭdēn'), heart muscle relaxant used to maintain regular heart rhythm patterns. It is an alkaloid chemically similar to quinine and, like quinine, occurs naturally in some species of cinchona trees. (Quinaglute, Quinidex, various generic), and rifampin, may increase the elimination rate of donepezil, resulting in decreased donepezil effectiveness. May have synergistic effects with neuromuscular-blocking medications, such as succinylcholine succinylcholine /suc·ci·nyl·cho·line/ (suk?si-nil-ko´len) a depolarizing neuromuscular blocking agent used as the chloride salt as an anesthesia adjunct and in convulsive therapy. (Anectine, Quelicin), or with cholinergic agonists, like bethanechol bethanechol /be·thane·chol/ (be-than´e-kol) a cholinergic agonist, used as the chloride salt to stimulate smooth muscle contraction of the urinary bladder in cases of postoperative, postpartum, or neurogenic atony and retention. (Urecholine, various generic). DRUG-FOOD INTERACTIONS May be taken with or without food. RECOMMENDED DOSE 5 mg once a day initially. The dose may be increased after four to six weeks to 10 mg once a day, if patient does not respond adequately to 5 mg daily dose. Dose should not be increased before this time. The 10 mg dose has been associated with greater adverse effects. These are less if the patient starts with 5 mg and the dose is subsequently increased to 10 mg as opposed to initiating therapy with 10 mg. DOSAGE FORMS AVAILABLE Tablets: 5 mg and 10 mg. MANUFACTURER Eisai/Pflzer OTHER POINTS OF INTEREST Should be used with caution in patients taking NSAIDs or with a history of GI bleeding. References (1.) Hutchison TA, Shahan DR, Anderson ML (Eds): DRUGDEX System. MIGROMEDEX, Inc., Englewood, Colorado (Edition expires 12/2000) (2.) Hebel SK, Katstrup EK (Eds): Drug Facts and comparisons. St. Louis, MO (2001) |
|
||||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion