Currently there is no cure for Alzheimer's disease but drug treatments may help with both the cognitive and behavioural symptoms. There are two types of medication used to treat Alzheimer's disease: acetylcholinesterase inhibitors and NMDA receptor antagonists.
Generally, people with Alzheimer's disease, have lower levels of acetylcholine and there is also a loss of nerve cells that use acetylcholine. Acetylcholine is a chemical substance that allows brain cells to communicate with one another.
Acetylcholinesterase inhibitors work by sending messages (in the form of electrical signals) between certain nerve cells. These inhibitors prevent acetylcholinesterase from breaking down acetylcholine in the brain, this supports increased the communication between nerve cells as a result of the increased levels of acetylcholine.
NMDA receptor antagonists, such as memantine, work quite differently from acetycholinerestrase inhibitors. In our brain we have another chemical called glutamate which also helps the communication between nerve cells. When the brain cells are damaged by Alzheimer's disease, excessive amounts of glutamate is released, which causes further damage. NMDA receptor antagonists protect the brain cells by blocking the effect of excess glutamate.