Although there is no cure, Alzheimer medications can temporarily slow the worsening of symptoms and improve quality of life for those with Alzheimer’s and their caregivers
The U.S. Food and Drug Administration (FDA) has approved five medications (listed below) to treat the symptoms of Alzheimer’s disease.
|Drug name||Brand name||Approved For||FDA Approved|
|1. donepezil||Aricept||All stages||1996|
|2. galantamine||Razadyne||Mild to moderate||2001|
|3. memantine||Namenda||Moderate to severe||2003|
|4. rivastigmine||Exelon||Mild to moderate||2000|
|5. tacrine||Cognex||Mild to moderate||1993|
To understand how Alzheimer’s medications work, you first need to understand the communication network in the brain. The picture below depicts nerve cells, or neurons, in the brain. Neurons are the chief cells destroyed by Alzheimer’s disease.
Roll your mouse over the red text to highlight the image.
In the brain, neurons connect and communicate at synapses, where tiny bursts of chemicals called neurotransmitters carry information from one cell to another. Alzheimer’s disrupts this process, and eventually destroys synapses and kills neurons, damaging the brain’s communication network.
Current FDA-approved Alzheimer drugs support this communication process through two different mechanisms:
1) Cholinesterase inhibitors work by slowing down the disease activity that breaks down a key neurotransmitter. Donepezil, galantamine, rivastigmine and tacrine are cholinesterase inhibitors.
2) Memantine,the fifth Alzheimer drug, is an NMDA (N-methyl-D-aspartate) receptor antagonist, which works by regulating the activity of glutamate, a chemical messenger involved in learning and memory. Memantine protects brain cells against excess glutamate, a chemical messenger released in large amounts by cells damaged by Alzheimer’s disease and other neurological disorders. Attachment of glutamate to cell surface “docking sites” called NMDA receptors permits calcium to flow freely into the cell. Over time, this leads to chronic overexposure to calcium, which can speed up cell damage. Memantine prevents this destructive chain of events by partially blocking the NMDA receptors.
On average, the five approved Alzheimer drugs are effective for about six to 12 months for about half of the individuals who take them.
Catalyst to progress
The first Alzheimer’s Association group of grants in 1982 included a study exploring the nerve cell communication network targeted by cholinesterase inhibitors, today’s mainstay of drug treatment. Association-funded work has contributed important insights to the knowledge base supporting virtually every FDA-approved and investigational Alzheimer treatment. Learn more about our commitment to research.
Researchers are looking for new ways to treat Alzheimer’s. Current drugs help mask the symptoms of Alzheimer’s, but do not treat the underlying disease. A breakthrough Alzheimer drug would treat the underlying disease and stop or delay the cell damage that eventually leads to the worsening of symptoms. Many experts believe such a breakthrough is possible within the next few years. There are several promising drugs in development and testing, but we need more volunteers to complete clinical trials of those drugs and increased federal funding of research to ensure that fresh ideas continue to fill the pipeline.