There is no cure for Alzheimer’s, but major research advances during the 2000s have produced two types of medicine that help relieve symptoms and temporarily improve mental functions. These medicines work by improving the communication between brain cells or by maintaining the health of the cells.
Cholinesterase inhibitors include Aricept, Razadyne and Exelon. These drugs work by helping to maintain levels of acetylcholine, a neurotransmitter (chemical messenger) that is essential for the brain to function properly. Acetylcholine is made by neurons (brain cells) to stimulate brain activity and help cell-to-cell communications that support brain functions including memory. Acetylcholine is broken down in the body by an enzyme called acetylcholinesterase. The cholinesterase inhibitor drugs prevent the breakdown and depletion of acetylcholine. Cholinesterase inhibitors are used primarily for patients with mild to moderate disease.
Another kind of drug, called a glutaminergic modulator, works based on a different neurotransmitter called glutamate. Namenda is a glutamineric moderator (also called an NMDA antagonist). Glutamate is involved in memory and reasoning. Researchers found that in Alzheimer’s patients, increased glutamate activity can impair the function of neurons. These drugs work by prevent the damaging effects of glutamate without interfering in its normal activity. Glutaminergic modulators are prescribed to help improve memory, reasoning, and performance of simple tasks in patients with moderate to severe Alzheimer’s. A once-daily dosage form of Namenda was approved in 2010.
These drugs are the first effective weapons in medicine’s arsenal to treat Alzheimer’s. They can preserve cellular function for a time, but they cannot stop the death of brain cells that progresses as Alzheimer’s advances. As research advances, new therapies are being developed not only to relieve symptoms but to change the disease process itself.
Cowen and Company, Therapeutic Categories Outlook 2012