Alzheimer's disease is complex, and it is unlikely that any one drug or other intervention can successfully treat it. Current approaches focus on helping people maintain mental function, manage behavioral symptoms, and slow or delay the symptoms of disease.
Several medications are approved by the U.S. Food and Drug Administration to treat symptoms of Alzheimer's. Donepezil (Aricept®), rivastigmine (Exelon®), and galantamine (Razadyne®) are used to treat mild to moderate Alzheimer's (donepezil can be used for severe Alzheimer's as well). Memantine (Namenda®), is used to treat moderate to severe Alzheimer's.
These drugs work by regulating neurotransmitters, the brain chemicals that transmit messages between neurons. They may help maintain thinking, memory, and communication skills and help with certain behavioral problems. However, these drugs don’t change the underlying disease process. They are effective for some but not all people and may help only for a limited time.
No published study directly compares the four approved drugs. Because they work in a similar way, it is not expected that switching from one of these drugs to another will produce significantly different results. However, a patient may respond better to one drug than another.
Common behavioral symptoms of Alzheimer’s include sleeplessness, wandering, agitation, anxiety, and depression. Scientists are learning why these symptoms occur and are studying new treatments—drug and nondrug—to manage them. Research has shown that treating behavioral symptoms can make people with Alzheimer’s more comfortable and makes things easier for caregivers.
See: "Medicines to Treat AD Symptoms and Behaviors" in Caring for a Person with Alzheimer's Disease
Alzheimer’s disease research has developed to a point where scientists can look beyond treating symptoms to think about addressing underlying disease processes. In ongoing clinical trials, scientists are developing and testing several possible interventions, including immunization therapy, drug therapies, cognitive training, physical activity, and treatments used for cardiovascular disease and diabetes.
For more information on current research on treatments, see "Testing Therapies to Treat, Delay, or Prevent Alzheimer's Disease".
People who want to help scientists test possible treatments may be able to take part in clinical trials, which are research studies that test the safety, side effects, and effectiveness of a medication or other intervention in humans. Study volunteers help scientists learn about the brain in healthy aging and in Alzheimer’s disease. Results of clinical trials are used to improve prevention and treatment approaches.
NIA sponsors many Alzheimer's disease clinical trials, including those conducted by Alzheimer's Disease Centers located throughout the United States. To find out more about clinical trials, talk with your health care provider or a memory or neurology clinic in your community. Or contact NIA’s ADEAR Center at 1-800-438-4380. You can also visit the Alzheimer’s Disease clinical trials finder. Additional clinical trials information is available at Volunteer for Alzheimer's Research and www.ClinicalTrials.gov.
This video explains Alzheimer’s disease and related clinical trials and the kinds of volunteers who are needed:
NIA launched the Alzheimer's Disease Cooperative Study (ADCS) in 1991 to develop and test new interventions and treatments for AD that might not otherwise be developed by industry. Operated under a cooperative agreement with the University of California, San Diego, the ADCS comprises more than 75 sites throughout the United States and Canada, and focuses on testing agents that lack patent protection, patented drugs that are marketed for other indications, and novel compounds developed by individuals, academic institutions, and small biotech companies. Read more about the ADCS »