In this drug factsheet:
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- abnormal dreams
- dryness of mouth
- eye irritation
- flushing of skin
- frequent urination
- hot flashes
- increase in sexual desire or performance
- increased sweating
- joint pain, stiffness, or swelling
- loss of appetite
- muscle cramps
- nasal congestion
- runny nose
- trouble sleeping
- unusual bleeding or bruising
- unusual tiredness or weakness
- weight loss
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- black, tarry stools
- bloody or cloudy urine
- blurred vision
- burning, prickling, or tingling sensations
- clumsiness or unsteadiness
- decreased, increased, difficult or painful urination
- high or low blood pressure
- increased and/or irregular heart rate
- loss of bowel control
- mood or mental changes, including abnormal crying, aggression, agitation, delusions, irritability, nervousness, or restlessness
- pain in chest, upper stomach, or throat
- problems with speech
- severe thirst
- shortness of breath
- sore throat
- tightness in chest
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Asthma and lung conditions: If you have lung conditions such as asthma or chronic obstructive pulmonary disease, discuss with your doctor how this medication may affect your medical condition, and whether any special monitoring is needed. Donepezil could cause symptoms of these conditions to worsen.
Chronic illness: In general, people with chronic medical conditions should be cautious when taking donepezil because of the increased risk of side effects. The benefits of taking the medication must be carefully weighed against the risks.
Epilepsy: There is a possibility that donepezil may increase the risk of seizures for susceptible people. If you have a history of seizure disorder, speak to your doctor about the risks and benefits of taking donepezil.
Heart disease: If you have heart disease such as active coronary artery disease and congestive heart failure, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Donepezil has the potential to slow the heart rate. People with cardiac conduction abnormalities (e.g., heart rhythm problems such as sick sinus syndrome) should not take donepezil.
Liver and kidney disease: Since little information exists on the use of donepezil by people with liver and kidney disease, your doctor may closely monitor you while taking this medication.
Stomach problems: Donepezil has the potential to cause an increase in the amount of acid that the stomach produces. If you have a history of ulcers or are at increased risk of developing stomach ulcers, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Pregnancy: The safety of donepezil for use during pregnancy has not been established. This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: The safety of donepezil for use while breast-feeding has not been established. Therefore, it should not be used by nursing women unless, in the opinion of their doctor, the potential benefits outweigh the risks.
Children: The safety and effectiveness of using this medication have not been established for children.
What other drugs could interact with this medication?
There may be an interaction between donepezil and any of the following:
- anticholinergic medications (e.g., atropine, hyoscyamine)
- barbiturates (e.g., phenobarbital)
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.