Patient Teaching Assignment: Donepezil PDF

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Patient Teaching Assignment: Donepezil...

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Patient Teaching Assignment: Donepezil Trent University NURS-3550H Dr. Mackie September 29, 2020

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Donepezil Pharmacology Alzheimer’s disease (AD) is an autoimmune disorder whose hallmarks includes the degeneration of neurons. Neurons that produce a signalling molecule called acetylcholine (ACh), known as cholinergic neurons, can be up to 90% below normal values in patients with severe AD as a result. Areas of the brain that largely undergo degeneration are the cerebral cortex and the hippocampus; these areas are high in cholinergic neurons. Memory, speech, perception, reasoning and other functions may decline alongside the loss of these neurons. Decreases in cholinergic neurons results in weaker ACh signalling in the cerebral cortex and hippocampus. Donepezil is a drug that helps maintain higher levels of acetylcholine. Donepezil is called a cholinesterase inhibitor. It reversibly binds to acetylcholinesterase (AChE) and prevents it from breaking down ACh. By preventing the breakdown of ACh, more of it remains in the area between neurons known as the synaptic cleft. Increasing the amount of acetylcholine between neurons will thereby boost those signals within the brain and help regions that have experienced degeneration. Donepezil is commonly used in patients with mild to moderate symptoms of AD and can be used with patients experiencing severe symptoms. Therapeutic effects of donepezil aim at improving functions such as memory, thought, reasoning, behaviour and function. Overall, the goal is to improve the quality of life for Mr. Jones. Donepezil is selective to cholinesterase in the central nervous system (i.e. the brain and spinal cord), however, acetylcholine has roles throughout the body. It has a long half-life of 70 hours, and as such, the medication is being gradually increased from 5mg to 10mg for Mr. Jones. At higher levels of donepezil, selectivity is reduced and there may be adverse effects. Nausea, vomiting, indigestion (dyspepsia) and diarrhea can occur; dizziness and headaches are common;

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narrowing of the airways (bronchoconstriction) occurs in the lungs; and a lowered heart rate (bradycardia) can occur in the heart, increases risks for fainting. Nursing Concerns On assessment, Mr. Jones is experiencing signs of malnourishment as evidenced by being 10lbs under his ideal body weight, complaints of fatigue, low albumin, dehydration, sluggish skin, and iron deficiency anemia. Some side effects of donepezil include nausea, vomiting and diarrhea. As such, his nutritional status may worsen by these effects on appetite. Donepezil is highly protein bound in the blood. When albumin is low, the bioavailability of the drug increases while undergoing rapid metabolization. It will be harder to keep donepezil within its therapeutic index and there will be a higher risk of encountering adverse effects. Fluids, and foods rich in iron should be encouraged such as beans, dark greens and meats. Where meal preparation from a caregiver or by Mr. Jones is not possible, supplements in iron and Boost/Ensure drinks are recommended. A referral to a speech language pathologist would assist in assessing swallowing difficulties and dysphagia that could affect Mr. Jones oral intake. Mr. Jones’ weight should be monitored daily ensure weight gain goals are being met. If Mr. Jones’ son is available for mealtime, providing companionship as well as helping to identify reasons for why Mr. Jones is not eating, as well as identifying when Mr. Jones’ appetite is largest is important. Mr. Jones’ last stool contained blood and his lab results came back with iron deficiency anemia; Mr. Jones is exhibiting blood loss. Regarding the use of donepezil this is a concern because one of the functions of ACh is to regulate gastric secretions. As systemic levels of ACh increase, gastric secretions increase, and thus, the pH in the GI decreases. A lower pH results in one of the side effects of donepezil, dyspepsia (indigestion). Dyspepsia may exacerbate the bleeding by creating or worsening peptic ulcers. Nursing interventions

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should include a GI assessment, the analysis of orthostatic hypotension, oxygen saturation, discussion with the physician to order haemoglobin and hematocrit labs, as well as patient education. Analysis of orthostatic hypotension, oxygen saturation and abnormal hemoglobin and hematocrit levels can help assess Mr. Jones’ blood volume and oxygenation, and patient education can help manage the bleeding. Patient education would include helping Mr. Jones and his son modify the diet to contain less alcohol, smoking, acidic and fatty foods (i.e. chocolate, coffee, deep fried foods), as well as the importance of avoiding ibuprofen. In addition, iron deficiency anemia decreases iron binding capacity leading to insufficient oxygenated red blood cells resulting in weakness and syncope due to hypoxemia. Risk for injury related to iron deficiency anemia as evidence by fatigue. Compounding this, donepezil can cause headaches, dizziness, and directly affect the heart by slowing it down causing bradycardia. Without adequate oxygenation and perfusion to the brain, Mr. Jones risks fainting, falling, and subsequently, fall related injuries such as fractures. Ensure that Mr. Jones and his son know about the side effects of donepezil and report any new or unusual symptoms not previously noted. Mr. Jones would benefit from a physician or occupational therapist referral to complete an assessment geared towards fall prevention, self-care and productivity. Follow-up appointments should be scheduled to monitor progress of medication, heart rate, and to assess new side effects. Knowing Mr. Jones’ baseline vitals and how he responds to donepezil will indicate if the drug is effective or if the dose is being tolerated. An increase in dose could be detrimental if previous assessments were unfavourable. Being aware of Mr. Jones’ medical history and prescribed, over the counter or natural medications are important. Drug interactions that block cholinergic signalling that results in reduced the therapeutic efficacy of donepezil should be avoided. Finally, immediately seek a physician if bleeding continues or worsens,

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References Burchum, J. R., & Rosenthal, L. D. (2019). Lehne’s pharmacology for nursing care (10th ed.). Elsevier....