Donepezil Side Effects
It is possible to develop certain side effects or problems while taking donepezil. Reactions that are most commonly reported include nausea, diarrhea, headache, and generalized pain. Some of the rare but possible side effects include dehydration, hot flashes, and sore throat. If you experience more serious side effects, such as fainting spells or uncontrollable movements, be sure to seek medical attention immediately.
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 be treated easily by you or your healthcare provider.
In previous research studies, up to 5 percent of people taking donepezil 5 mg, up to 13 percent of people taking donepezil 10 mg daily, and up to 18.6 percent of people taking donepezil 23 mg once 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 with you.)
There are a number of side effects with donepezil that you should report immediately to your healthcare provider. These side effects include but are not limited to:
- Severe diarrhea
- Severe nausea or vomiting
- Unexplained weight loss
- Stomach pain
- Changes in vision or balance
- Fainting spells
- Nervousness or agitation
- Uncontrollable movements
- Slow heartbeat
- Difficulty passing urine
- Worsening of asthma
- Stomach ulcers or intestinal ulcers
- Signs of an allergic reaction, such as an unexplained rash, hives, itching, swelling of the mouth or throat, wheezing, or difficulty breathing.