Donepezil Side Effects: An Introduction
As with any medicine, there are possible side effects with
donepezil (
Aricept®). However, not everyone who takes donepezil will have side effects. In fact, most people tolerate the medication well. When side effects do occur, they are generally minor and either require no treatment or can easily be treated by you or your healthcare provider.
In previous research studies, up to 5 percent of people taking donepezil 5 mg and 13 percent of people taking donepezil 10 mg daily stopped their medicine because of side effects. Nausea, vomiting, and
diarrhea were the most common reasons why people stopped taking donepezil. Side effects tend to be less severe if the dose is slowly increased over a period of several weeks.
(The side effects discussed below are not a complete list of side effects reported with donepezil. Your healthcare provider can discuss a more complete list of possible side effects with you.)
Common Side Effects of Donepezil
Donepezil has been studied thoroughly in clinical trials. In these studies, side effects are always documented and compared to those that occur in a similar group of people not taking the medicine. This way, it is possible to see what side effects occur, how often they appear, and how they compare to the group not taking the medicine.
Based on these studies, the most common side effects with donepezil were:
- Nausea -- up to 11 percent
- Diarrhea -- up to 10 percent
- Headache -- up to 10 percent
- Insomnia -- up to 9 percent
- Generalized pain -- up to 9 percent
- Dizziness -- up to 8 percent.
Other donepezil side effects occurring in more than 2 percent of the people included:
- Muscle cramps
- Vomiting
- Fatigue
- Loss of appetite
- Skin discoloration
- Decrease in weight
- Depression
- Abnormal dreams
- Arthritis
- Fainting
- Tiredness
- Frequent urination.
