Cholinesterase inhibitors for Alzheimer's disease
Examples
Generic Name Brand Name donepezil Aricept galantamine Reminyl rivastigmine Exelon How It Works
Cholinesterase inhibitors increase the level of a brain chemical called acetylcholine. People with Alzheimer's disease and related conditions have decreased brain levels of this neurotransmitter. Increasing the amount of acetylcholine appears to slow mental decline in people with Alzheimer's disease.
These medications help the brain cells work better but do not stop or reverse the destruction of brain cells and loss of acetylcholine that occur in Alzheimer's disease. They do not prevent the disease from getting worse but may slow the progression of symptoms.
Why It Is Used
Cholinesterase inhibitors may be used to treat some symptoms of moderately severe Alzheimer's disease. They also may be used in other types of dementia, such as dementia with Lewy bodies and multi-infarct dementia.
How Well It Works
Cholinesterase inhibitors may produce small improvements in memory and general ability to function.1 For example, the person may be able to remember friends' names better and be able to dress himself or herself with less difficulty. They may also modestly improve behavioural symptoms and improve the person's ability to function.2
- Studies have shown that people with mild to moderately severe Alzheimer's who took donepezil scored somewhat higher in their doctors' evaluations of their mental and functional status than those who did not take the drug.
- Studies show that rivastigmine has beneficial effects similar to donepezil. Rivastigmine has more side effects, including nausea and possible weight loss. Rivastigmine does not appear to cause interactions with other medications, as the other cholinesterase inhibitors do.3
- Galantamine is available in Canada. It may improve memory and thinking abilities.
- Improvement with cholinesterase inhibitors usually is minimal. The person's mental status does not stabilize, but the rate of decline may be somewhat slower than it would be without the medication.
- Improvement in symptoms may be more likely at higher doses, but higher doses also may cause more side effects.
- Cholinesterase inhibitors may improve behavioural disturbances. People who have improved thinking and memory abilities may also have improved behaviour, although this is not always the case.
- Cholinesterase inhibitors may have some use in other dementias, such as dementia with Lewy bodies and multi-infarct dementia.
Cholinesterase inhibitors do not help everyone who has Alzheimer's disease. It is believed that as the disease progresses, the medication eventually may stop working.
The various cholinesterase inhibitors have similar effects on memory and cognitive function, so the choice between medications may be based on side effects, dosing schedules and ease of use, individual response to a particular medication, or other factors.
Side Effects
In general, most people seem to tolerate cholinesterase inhibitors very well. The most common side effects are:
- Nausea.
- Diarrhea.
- Vomiting.
- Indigestion.
- Abdominal pain.
- Loss of appetite and weight loss.
Less common side effects include insomnia, fatigue, and muscle cramps. Side effects tend to be mild and usually go away within a few weeks after treatment with the medication is started.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
Cholinesterase inhibitors do not work for everyone who has Alzheimer's disease, but they are helpful for some people. They may be a reasonable option for those who understand the risks and costs and feel the possible benefits are worth it.
A study that compared the results of other studies looking at cholinesterase inhibitors for people with Alzheimer's disease found that the benefits of taking them are small.4
Side effects seem to be milder and occur less often with donepezil or galantamine than with rivastigmine.
Experts agree that reducing problems with memory loss may help people with Alzheimer's disease live better. In some cases, reducing these problems may help people live more independently for a longer period of time.
Complete the new medication information form (PDF)
(What is a PDF document?) to help you understand this medication.
| Author: | Douglas Dana Sabra L. Katz-Wise Ralph Poore | Last Updated: January 26, 2007 |
| Medical Review: | Adam Husney, MD - Family Medicine Andrew Swan, MD, CCFP, FCFP - Family Medicine Peter J. Whitehouse, MD - Neurology | |
 | ||
| |
| Topic Contents | |
| Examples | |
| How It Works | |
| Why It Is Used | |
| How Well It Works | |
| Side Effects | |
| What To Think About | |
| References | |