Donepezil is a medication commonly prescribed to older adults to help manage symptoms of Alzheimer’s disease and other types of dementia. While it can improve memory and thinking, it also comes with a range of possible side effects, especially in older adults who may be more sensitive to its effects.
One of the most frequent side effects is gastrointestinal discomfort. Many patients experience nausea, vomiting, diarrhea, or loss of appetite, particularly when starting the medication or increasing the dose. These symptoms often improve over time as the body adjusts. However, donepezil can increase stomach acid, which may raise the risk of stomach ulcers or bleeding, especially at higher doses or when combined with certain pain relievers like NSAIDs.
Donepezil can also affect the heart. It may cause a slower heartbeat (bradycardia), which can lead to dizziness, fainting, or fatigue. This is particularly important for older adults who might already have heart conditions. If a significant slowing of the heart rate occurs, the medication may need to be stopped. Donepezil can also cause other cardiovascular issues such as lightheadedness or conduction abnormalities.
Urinary problems are another concern. Some older adults taking donepezil report increased urinary frequency or urgency. This happens because donepezil increases acetylcholine, a chemical that affects bladder muscles. Sometimes, medications to treat these urinary symptoms are prescribed, but they can interfere with donepezil’s benefits and cause additional side effects like confusion or constipation.
Sleep disturbances are common as well. Donepezil can cause insomnia, vivid dreams, or nightmares, especially when taken at night. Switching the dose to daytime may help reduce these problems.
Other side effects include muscle cramps, fatigue, headaches, dizziness, and drowsiness. While these are usually mild, they can affect quality of life and increase the risk of falls in older adults. Rare but serious side effects include seizures, severe allergic reactions, or signs of overdose such as severe nausea, muscle weakness, or breathing difficulties.
Because older adults often have other health issues like lung disease, kidney problems, or a history of seizures, donepezil must be used cautiously. It can worsen breathing problems in people with asthma or chronic obstructive pulmonary disease (COPD). Kidney or liver impairment can also affect how the drug is processed, increasing the chance of side effects.
Doctors usually start donepezil at a low dose and increase it slowly to minimize side effects. Regular monitoring is important to catch any problems early, especially heart rate changes or worsening urinary symptoms. Patients and caregivers should report any new or worsening symptoms to their healthcare provider promptly.
Sources
https://www.psychdb.com/meds/dementia/donepezil
https://www.goodrx.com/donepezil/what-is
https://www.mayoclinic.org/drugs-supplements/memantine-and-donepezil-oral-route/description/drg-20137323
https://www.meded101.com/donepezil-urinary-frequency-and-bradycardia/
https://www.droracle.ai/articles/442132/what-is-patient-education-on-aricept
https://www.israelpharm.com/faq/does-insurance-typically-cover-aricept-for-alzheimers-and-what-helps-with-coverage-gaps/
https://alzheimer.ca/en/about-dementia/dementia-treatment-options-developments/medications-for-alzheimers
