Donepezil, also known as donepezil hydrochloride, is a medication used to treat Alzheimer’s disease, from mild to severe stages. It works by increasing levels of acetylcholine in the brain, a chemical involved in transmitting nerve signals.
Acetylcholine levels may be reduced in people with Alzheimer’s disease as the nerve cells that produce it become damaged. Increasing acetylcholine levels can help improve certain symptoms, although donepezil does not cure or stop the progression of Alzheimer’s disease.
Donepezil is available in the United States by prescription in tablet form, including 5 mg and 10 mg strengths. It should be taken only as directed by a doctor, at the prescribed dose and for the recommended length of treatment.
What is donepezil used for?
Donepezil is used to treat Alzheimer’s disease, including mild, moderate, and severe stages.
This medication works by increasing the concentration of acetylcholine in the brain. Acetylcholine is an important neurotransmitter that helps transmit nerve signals and supports normal brain function, and its levels may decrease in Alzheimer’s disease as the neurons that produce it degenerate.
By increasing acetylcholine levels in the brain, donepezil can help reduce some symptoms of Alzheimer’s disease. However, it does not cure Alzheimer’s disease.
How to take donepezil
Donepezil is taken by mouth once a day, usually in the evening before bedtime. It can be taken with or without food and should be used at the time recommended by a doctor.
For adults with mild to moderate Alzheimer’s disease, the usual dose is 5 to 10 mg once a day. Treatment generally begins with 5 mg once daily, and the dose may be increased to 10 mg once daily after at least 4 to 6 weeks of treatment with the lower dose.
For moderate to severe Alzheimer’s disease, the dose is determined by the doctor based on the person’s treatment plan and response.
If a dose is missed and it is almost time for the next dose, the missed dose should be skipped and the next dose taken at the usual time. Two doses should not be taken at the same time to make up for a missed dose.
Donepezil should always be taken under medical supervision. The doctor may adjust the dose or stop treatment depending on how the person responds.
Possible side effects
The most common side effects that may occur during treatment with donepezil include headache, diarrhea, nausea, pain, accidental injury, fatigue, fainting, vomiting, loss of appetite, muscle cramps, insomnia, dizziness, common cold symptoms, and abdominal problems.
Donepezil may cause serious allergic reactions that require immediate medical attention. Treatment should be stopped and emergency medical care should be sought if symptoms such as difficulty breathing, coughing, a feeling that the throat is closing, or swelling of the mouth, tongue, or face occur.
Emergency medical care should also be sought if symptoms such as a slow heartbeat, severe dizziness or feeling faint, stomach pain, heartburn, fever, seizures, pain or difficulty urinating, breathing problems, blood in the stool, coughing up blood, or vomit that looks like coffee grounds occur.
Who should not take donepezil?
Donepezil should not be taken by anyone who is allergic to donepezil, piperidine derivatives, or any of the ingredients in the medication.
The safety and effectiveness of donepezil have not been established in children. People who are pregnant, planning to become pregnant, or breastfeeding should tell their doctor before taking donepezil so that the potential risks and benefits can be evaluated.
A doctor should also be told about all other medications, vitamins, and supplements being taken to reduce the risk of drug interactions.