Cholinesterase inhibitors donepezil

Like other cholinesterase inhibitors, donepezil carries the risk of cholinergic side effects. In fact, if the dose of a cholinesterase inhibitor is increased too rapidly, it may even worsen behavior. The principal side effects of donepezil include upset stomach, diarrhea, headache, and dizziness. It is usually started at 5 mg taken once daily in the evening. After 1 month, the dose of donepezil can be increased to lOmg/day. 

Cholinesterase inhibitors donepezil hydrochloride galantamine hydrobromide rivastigmine tartrate... 

FIGURE 12—24. Icon for the cholinesterase inhibitor donepezil. This is the current first-line treatment for Alzheimer s disease, since it is a once daily agent without significant hepatotoxicity. It is a reversible agent, selective for acetylcholinesterase (AChE) over butyrylcholinesterase (BuChE), developed by American and Japanese companies. 

The family member of a client diagnosed with early-stage Alzheimer s disease (AD) who was prescribed the cholinesterase inhibitor donepezil (Aricept) without improvement asks the nurse, Can anything be done to slow the disease since this medication does not work Which statement is the nurse s best response ... 

Tacrine is particularly damaging to the liver and can result in hepatotoxicity. Because tacrine is more likely to cause adverse reactions and drug interactions, it must be administered more frequently (4 times a day) and is rarely used in current therapy. Donepezil has fewer and milder side effects than tacrine It is considered the agent of first choice However, some patients may achieve a better response with one drug than another. Additional adverse reactions are listed in the Summary Drug Table Cholinesterase Inhibitors. 

Until recently there was no effective pharmacological treatment for Alzheimer s disease. Cholinesterase inhibitors are now available, but their effects are relatively small and only a proportion of patients respond (Burns et al, 1999). How should pharmacological budgets be spent on patients at the end of their life, and who should benefit when the improvements are small Most studies showed that donepezil gave a net... 

Donepezil is a piperidine cholinesterase inhibitor, which reversibly and non-competitively inhibits centrally active acetylcholinesterase 34 This specificity is claimed to result in fewer peripheral side effects as compared to the other ChE inhibitors. 

Adverse reactions with donepezil include nausea, vomiting, and diarrhea. These are typical cholinergic side effects to expect with all of the cholinesterase inhibitors. Table 32-6 compares the major side effects for all of the approved agents for Alzheimer s disease.34-38... 

Donepezil (Aricept). Donepezil is the second cholinesterase inhibitor approved for the treatment of dementia. Most physicians find it much easier to use than its predecessor. It can be given once a day and carries none of the risk of liver toxicity seen with tacrine. It has been shown in multiple clinical trials to delay the decline in cognitive function in patients with Alzheimer s disease. 

Anesthesia Donepezil, as a cholinesterase inhibitor, is likely to exaggerate succinylcholine-type muscle relaxation during anesthesia. 

Drugs that may affect donepezil are CYP450 3A4 and 2D6 inhibitors (eg, ketoconazole, quinidine) and CYP450 3A4 and 2D6 inducers (eg, carbamazepine, dexamethasone, phenobarbital, phenytoin, rifampin). Drugs that may be affected by donepezil include anticholinergics, cholinometics/cholinesterase inhibitors, NSAIDs. 

Donepezil, rivastigmine and galanfamine are the three available cholinesterase inhibitor (ChEI) and all work by inhibiting the breakdown of acetylcholine, an important neurotransmitter associated with memory, by blocking the enzyme. 

Clinicians often use each cholinesterase inhibitor in combination with memantine however, the best evidence to date for such combination treatment is the use of memantine in patients with moderate to severe Alzheimer s disease already taking donepezil (Tariot et al. 2004). 

Nathan, P.J., Baker, A., Carr, E., et ah Cholinergic modulation of cognitive function in healthy subjects acute effects of donepezil, a cholinesterase inhibitor. Hum. Ptychopharmacol. 16, 481-483, 2001. 

The beneficial effect of precursors (e.g., lecithin), cholinesterase inhibitors (e.g., physostigmine, donepezil), or drugs with cholinomimetic effects (e.g., bethanechol) for actue mania was discovered in part from the work of Janowsky et al. ( 29), leading to their cholinergic—noradrenergic balance hypothesis. Interestingly, lithium is also able to raise RBC choline concentrations and CNS cholinergic activity ( 274). 

Tacrine was the first cholinesterase inhibitor approved for the enhancement of memory associated with Alzheimer s disease in the United States. Because of its short half-life, drug interactions, and hepatic toxicity, it is currently considered second-line therapy for patients who fail to respond to donepezil. Its psychophar-... 

FIGURE 12-30. Alzheimer s disease pharmacy. Currently, donepezil is first-line for memory loss, and atypical antipsychotics (SDA) are first-line for positive psychotic symptoms together they may work synergistically. Soon the cholinesterase inhibitors metrifonate and/or rivastigmine may become available. Second-line treatments are tacrine for memory and conventional antipsychotics (D2) for positive psychotic symptoms. Several other agents are in clinical and preclinical development. 

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