Home > Patients & Visitors > Health Library > Alzheimer's Disease
Alzheimer's disease is the most common cause of mental decline, or dementia. But dementia also has many other causes. For more information, see the topic Dementia.
Alzheimer's disease damages the brain. It causes a steady loss of memory and of how well you can speak, think, and do your daily activities.
Alzheimer's disease gets worse over time, but how quickly this happens varies. Some people lose the ability to do daily activities in the first few years. Others may do fairly well until much later in the disease.
Mild memory loss is common in people older than 60. It may not mean that you have Alzheimer's disease. But if your memory is getting worse, see your doctor. If it is Alzheimer's, treatment may help.
Alzheimer's disease happens because of changes in the brain. Some of the symptoms may be related to a loss of chemical messengers in the brain, called neurotransmitters, that allow nerve cells in the brain to communicate properly.
People with Alzheimer's disease have two things in the brain that are not normal: amyloid plaques and neurofibrillary tangles. Experts don't know if amyloid plaques and neurofibrillary tangles are side effects of Alzheimer's disease or part of the cause.
For most people, the first symptom of Alzheimer's disease is memory loss. Often the person who has a memory problem doesn't notice it, but family and friends do. But the person with the disease may also know that something is wrong.
The symptoms of Alzheimer's get worse slowly over time. You may:
A person who gets these symptoms over a few hours or days or whose symptoms suddenly get worse needs to see a doctor right away, because there may be another problem.
Your doctor will ask about your past health and do a physical exam. He or she may ask you to do some simple things that test your memory and other mental skills. Your doctor may also check how well you can do daily tasks.
The exam usually includes blood tests to look for another cause of your problems. You may have tests such as CT scans and MRI scans, which look at your brain. By themselves, these tests can't show for sure whether you have Alzheimer's.
There is no cure for Alzheimer's disease. But there are medicines that may slow symptoms down for a while and make the disease easier to live with. These medicines may not work for everyone or have a big effect. But most experts think they are worth a try.
As the disease gets worse, you may get depressed or angry and upset. The doctor may also prescribe medicines to help with these problems.
If you are or will be taking care of a loved one with Alzheimer's, start learning what you can expect. This can help you make the most of the person's abilities as they change. And it can help you deal with new problems as they arise.
Work with your loved one to make decisions about the future before the disease gets worse. It's important to write a living will and a durable power of attorney.
Your loved one will need more and more care as the disease gets worse. You may be able to give this care at home. Or you may want to think about using assisted living or a nursing home.
Ask your doctor about local resources such as support groups or other groups that can help as you care for your loved one. You can also search the Internet for online support groups. Help is available.
Health Tools help you make wise health decisions or take action to improve your health.
Alzheimer's disease causes loss of brain cells in areas of the brain. Some of the symptoms may be related to a loss of chemical messengers in the brain, called neurotransmitters, that allow nerve cells in the brain to communicate properly.
People with Alzheimer's disease have two things in the brain that are not normal: amyloid plaques and neurofibrillary tangles.
Experts don't know if amyloid plaques and neurofibrillary tangles are side effects of Alzheimer's disease or part of the cause.
Memory loss is usually the first sign of Alzheimer's disease. Having some short-term memory loss in your 60s and 70s is common, but this doesn't mean it's Alzheimer's disease.
Compare these examples of normal memory problems and the types of memory problems that may be caused by Alzheimer's disease.
In normal forgetfulness, the person may forget:
In Alzheimer's disease, the person may forget:
Parts of an experience.
An entire experience.
Where the car is parked.
What the car looks like.
A person's name, but remember it later.
Ever having known a particular person.
Alzheimer's disease also causes changes in thinking, behavior, and personality. Close family members and friends may first notice these symptoms, although the person may also realize that something is wrong.
Following are some of the symptoms of the different stages of Alzheimer's disease. They vary as the disease progresses. Talk to your doctor if a friend or family member has any of the signs.
Usually, a person with mild Alzheimer's disease:
These symptoms often are more obvious when the person is in a new and unfamiliar place or situation.
Some people have memory loss called mild cognitive impairment. People with this condition are at risk for Alzheimer's disease or another type of dementia. But not all people with mild cognitive impairment progress to dementia.
With moderate Alzheimer's disease, a person typically:
With severe Alzheimer's disease, a person usually:
Early in the disease, Alzheimer's usually doesn't affect a person's fine motor skills (such as the ability to button or unbutton clothes or use utensils) or sense of touch. So a person who develops motor symptoms (such as weakness or shaking hands) or sensory symptoms (such as numbness) probably has a condition other than Alzheimer's disease. Conditions such as Parkinson's disease, for instance, may cause motor symptoms along with dementia.
Other conditions with symptoms similar to those of Alzheimer's disease may include:
Researchers have discovered changes that take place in the brains of people who have Alzheimer's disease. These brain changes may cause the memory loss and decline in other mental abilities that occur with Alzheimer's disease. It's not fully understood why these brain changes occur in some people but not in others.
Alzheimer's disease gets worse over time, but the course of the disease varies from person to person. Some people may still be able to function relatively well until late in the course of the disease. Others may lose the ability to do everyday activities very early on.
A person with severe dementia becomes more vulnerable to other illnesses, such as pneumonia.
Certain things make getting a disease more likely. These are called risk factors. Risk factors for Alzheimer's disease include:
Alzheimer's disease tends to develop slowly over time. If confusion and other changes in mental abilities come on suddenly, within hours or days, the problem may be delirium. Delirium needs treatment right away.
Seek care now if:
Call your doctor to schedule an appointment if:
If memory loss isn't quickly getting worse or interfering with work, social life, or the ability to function, it may be normal age-related memory loss. Talk to your doctor if you are concerned about memory loss.
Alzheimer's disease is diagnosed after other conditions are ruled out. Your doctor will use a variety of tests to do this.
It usually is helpful to have a family member or someone in close contact with the person present at the appointment. A family member may be able to provide the best information about how a person's day-to-day functioning, memory, and personality have changed.
The doctor will use a medical history and physical exam to help find out if a physical problem may be causing the person's symptoms. Sometimes another problem can cause the same symptoms as Alzheimer's.
The person will also have a functional status exam and a mental health assessment. During these exams, he or she will be asked to perform simple tasks.
Lab tests may be done to rule out other possible causes of a person's symptoms, such as levels of certain minerals or chemicals in the blood, liver disease, abnormal thyroid levels, or nutritional problems, such as folate or vitamin B12 deficiencies. Treatment for these conditions may slow or reverse mental decline.
Blood tests that may be done include:
Other tests include:
In some cases, examining the brain after death is done if the family wants to confirm that the person had Alzheimer's disease.
While there is not yet a cure for Alzheimer's disease, you can create a care plan to maintain quality of life and help the person stay active.
As you get started, ask yourself, other family members, and your doctor these questions:
Care plans may include any of the following:
See Home Treatment to learn more about helping the person remain independent, making the most of the person's abilities, and dealing with new problems as they arise.
An important part of treatment is finding and treating other medical problems the person may have.
At this time, there is no known way to prevent Alzheimer's disease. But there are things that may make it less likely.
Adults who are physically active may be less likely than adults who aren't physically active to get Alzheimer's disease or another type of dementia. Moderate activity is safe for most people, but it's always a good idea to talk to your doctor before starting an exercise program.
Older adults who stay mentally active may be at lower risk for Alzheimer's disease. Reading, playing cards and other games, working crossword puzzles, and even watching television or listening to the radio may help them avoid symptoms of the disease. So can going out and remaining as socially active as possible. Although this "use it or lose it" approach hasn't been proved, no harm can come from regularly putting the brain to work.
People who eat more fruits and vegetables, high-fiber foods, fish, and omega-3 rich oils (sometimes known as the Mediterranean diet) and who eat less red meat and dairy may have some protection against dementia.
Most people who have Alzheimer's disease are cared for at home by family members and friends. Taking care of someone with the disease can be physically and emotionally draining, but there are ways to make it easier.
Home treatment involves teamwork among health professionals and caregivers to create a safe and comfortable environment and to make tasks of daily living as easy as possible. Some people with early or mild Alzheimer's disease can be involved in planning for the future and organizing the home and daily tasks.
One of the keys to successful home care is educating yourself. You can do a lot to make the most of the person's remaining abilities, manage the problems that develop, and improve the quality of his or her life as well as your own. Also remember that caregiving can be a positive experience for you and the person you are caring for.
Work with the team of health professionals to:
The team can also help you learn how to manage behavior problems. For example, you can learn ways to:
Caregivers should remember to seek support from other family and friends. Groups such as the Alzheimer's Association and the Dementia Advocacy and Support Network can provide not only educational materials but also information on support groups and services. For more information, see the topic Caregiver Tips.
As Alzheimer's disease progresses, you have decisions to make about medical care and legal issues.
There are no medicines that can prevent or cure Alzheimer's disease. Medicine may help some people function better by temporarily reducing memory loss and thinking problems. Other medicines may be needed to manage behaviors or symptoms that are causing strain for the person who has Alzheimer's disease and/or for his or her caregivers.
Because these medicines work differently, they are sometimes used together (for example, memantine and donepezil).
These medicines may temporarily help improve memory and daily functioning in some people who have Alzheimer's disease. The improvement varies from person to person. These medicines don't prevent the disease from getting worse. But they may slow down symptoms of mental decline.
The main decision about using these usually isn't whether to try a medicine but when to begin and stop treatment. Treatment can be started as soon as Alzheimer's disease is diagnosed. If the medicines are effective, they are continued until the side effects outweigh the benefits or until the person no longer responds to the medicines.
Other medicines may be tried to treat anxiety, agitated or hostile behavior, sleep problems, frightening or disruptive false beliefs (delusions), suspicion of others (paranoia), or hallucinations (seeing or hearing things that aren't there).
Before deciding to use medicine for behavior problems, try to see what is causing the behavior. If you know the cause, you may be able to find better ways of dealing with that behavior. You may be able to avoid treatment with medicine and the side effects and costs that come with it.
Medicines generally are used only for behavior problems when other treatments have failed. They may be needed if:
Close monitoring and regular reevaluation of the person who has Alzheimer's disease are very important during treatment with medicine. As the disease progresses and symptoms change, the person's medicine needs often change. If you are a caregiver for someone with Alzheimer's disease, be alert for adverse drug reactions or side effects that further impair the person's ability to function.
Other therapies, such as light therapy, aromatherapy, and exercise, may help reduce behaviors such as agitation. But they should only be done with supervision.
Another way a caregiver can try to reduce agitation in a person who has Alzheimer's disease is to play soothing music during meals and when the caregiver is helping with bathing.
Other treatments for Alzheimer's disease need further study. Their effectiveness and possible side effects aren't yet fully known. Talk to your doctor before you decide to try any herbal therapies, supplements, or nonprescription treatments.
Current as of:
June 16, 2021
Author: Healthwise StaffMedical Review: Anne C. Poinier MD - Internal MedicineKathleen Romito MD - Family MedicineAdam Husney MD - Family MedicineElizabeth T. Russo MD - Internal MedicineMyron F. Weiner MD - Psychiatry, Neurology
Current as of: June 16, 2021
Author: Healthwise Staff
Medical Review:Anne C. Poinier MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Adam Husney MD - Family Medicine & Elizabeth T. Russo MD - Internal Medicine & Myron F. Weiner MD - Psychiatry, Neurology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2022 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.