Donepezil is used to treat dementia (a brain disorder that affects the ability to remember, think clearly, communicate, and perform daily activities and may cause changes in mood and personality) associated with Alzheimer's disease (AD; a brain disease that slowly destroys the memory and the ability to think, learn, communicate and handle daily activities). Donepezil is in a class of medications called cholinesterase inhibitors. It improves mental function (such as memory, attention, social interaction, reasoning and language abilities, and ability to perform activities of daily living) by increasing the amount of a certain naturally occurring substance in the brain. Donepezil may improve the ability to think and remember or slow the loss of these abilities in people who have AD. However, donepezil will not cure AD or prevent the loss of mental abilities at some time in the future.
Donepezil comes as a tablet and an orally disintegrating tablet (tablet that dissolves quickly in the mouth) to take by mouth. It is usually taken once a day, in the evening at bedtime, with or without food. Take donepezil at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. It may take awhile before you experience the full benefits of donepezil. Take donepezil exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Donepezil helps control the symptoms of Alzheimer's disease but does not cure it. Continue to take donepezil even if you feel well. Do not stop taking donepezil without talking to your doctor.
Your doctor may start you on a low dose of donepezil and increase your dose after 4 to 6 weeks.
To take the orally disintegrating tablet, place the tablet on your tongue. The tablet will quickly dissolve and can be followed with a drink of water.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
Before taking donepezil,
- tell your doctor and pharmacist if you are allergic to donepezil or any other medications.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: antihistamines; aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) and naproxen (Aleve, Naprosyn); bethanechol (Duvoid, Urabeth, Urecholine); carbamazepine (Tegretol); dexamethasone (Decadron, Dexone); ipratropium (Atrovent); ketoconazole (Nizoral); medications for glaucoma, irritable bowel disease, motion sickness, myasthenia gravis, Parkinson's disease, ulcers, or urinary problems; phenobarbital (Luminal, Solfoton); phenytoin (Dilantin); quinidine (Quinidex); and rifampin (Rifadin, Rimactane). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had gastrointestinal (GI) bleeding; an ulcer,asthma, or obstructive pulmonary disease (chronic bronchitis or emphysema), or heart disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking donepezil, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking donepezil.
Unless your doctor tells you otherwise, continue your normal diet.
If you forget to take a dose of donepezil, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you do not take donepezil, for 1 week or longer, you should call your doctor before starting to take this medication again.
Donepezil may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- loss of appetite
- weight loss
- frequent urination
- muscle cramps
- joint pain, swelling, or stiffness
- excessive tiredness
- changes in behavior
- abnormal dreams
- difficulty falling asleep or staying asleep
- discoloration or bruising of the skin
- red, scaling, itchy skin
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:
- slow heartbeat
- chest pain
- black or tarry stools
- red blood in stools
- bloody vomit
- vomit that looks like coffee grounds
- inability to control urination
- difficulty urinating or pain when urinating
- lower back pain
Donepezil may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Symptoms of overdose may include:
- slow heartbeat
- difficulty breathing
- muscle weakness
Keep all appointments with your doctor.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Last Reviewed: September 1, 2010.