Related topics: •  Alzheimer's Disease

Ten years ago, the only thing doctors could give patients with Alzheimer's disease was their sympathy and support. Today, they can also offer real hope. There's still no cure for Alzheimer's, but new medications can slow down the disease and improve the lives of many patients. Other promising treatments are just over the horizon.

Here's a look at the most common treatments for Alzheimer's, along with new areas of research. Several of the drugs discussed below -- Razadyne, Aricept, and Exelon -- are cholinesterase inhibitors, designed to improve memory and reasoning by influencing chemical processes in the brain. Although the changes may be subtle, it's thought that these drugs can slow the deterioration of memory in many patients -- especially if they are used early in the disease process. An earlier Alzheimer's drug, tacrine (Cognex), had the potential to harm the liver and is rarely prescribed today.

Approved by the Food and Drug Administration in 2001, Razadyne (formerly called Reminyl), is one of the newest treatments for Alzheimer's disease. Like the next two drugs on this list, Razadyne works by protecting the brain's supply of acetylcholine, a chemical that carries messages between brain cells. (It does this in part by halting the activity of an enzyme with the formidable name of acetylcholinesterase, which slows the breakdown of the message-carrying acetylcholine.) Unlike other drugs, Razadyne also seems to increase the production of acetylcholine and makes brain cells more receptive to the chemical.

How it's thought to help: Studies show that many patients with Alzheimer's who take Razadyne can enjoy modest gains in their memory or thinking skills. The drug may also temporarily help put the brakes on the disease. In a 2004 study of 285 patients with Alzheimer’s and dementia, those taking galantamine showed improvement in cognition at 6 months and significant improvement at 12 months. In a placebo group who switched to galantamine, cognitive function also improved, but not to the level attained by patients who had been treated with the drug for the entire 12 months.

How it's taken: Razadyne comes in both liquid and tablet form. Most patients start at a dose of 4 milligrams twice daily. Over the next eight weeks, the dose is slowly increased to either 8 or 12 milligrams or more twice daily. There is also a once-daily formulation of this drug.

Side effects: Razadyne appears to be a very safe drug. It often causes mild side effects, including upset stomach, vomiting, diarrhea, and dizziness. Patients can help protect their stomachs by taking the drug with meals and drinking six to eight glasses of water every day.

Approved in 2000, Exelon works by enhancing acetylcholine in the brain.

How it's thought to help: In clinical trials, Exelon slightly increased the memory and thinking skills of some patients with mild to moderate Alzheimer's disease. Unfortunately, more than half of all patients showed no improvement.

How it's taken: Exelon is available as a capsule, a liquid, or a patch. In oral form, most patients start at a small dose of 1.5 milligrams, two times a day. Over the next four weeks, the dosage then gradually increases to somewhere between 6 and 12 milligrams daily, in divided doses. The gradual increase in dosage helps lower the risk of side effects.

Side effects: Possible side effects of Exelon include nausea, vomiting, and diarrhea. Side effects are more common at higher doses.

Approved in 1997, this close relative of Exelon and Razadyne is still commonly prescribed to patients with mild to moderate Alzheimer's. In 2006 the Food and Drug Administration approved Aricept for severe Alzheimer's, making it the first drug to be approved for the treatment of all stages of the disease.

How it's thought to help: Like Exelon, Aricept has been shown to slightly boost the thinking and memory skills of some patients. Fewer than half of all patients show any improvement.

How it's taken: Most people start with one 5-milligram tablet every day. If there aren't any side effects, the dose can be upped to 10 milligrams each day.

Side effects: Patients taking Aricept often notice mild side effects such as nausea, diarrhea, and vomiting. Other possible side effects include insomnia, muscle cramps, fatigue, and loss of appetite. These problems usually fade over time even if the patient stays on the same dose.

This drug, which was approved by the Food and Drug Administration in 2003, is the first medication that has been shown to help people with severe Alzheimer's disease. It appears to work by restoring the brain's balance of glutamate, a chemical that plays a key role in memory and learning. The FDA recommends memantine for moderate to severe Alzheimer's. How it's thought to help: In a six-month study published in the New England Journal of Medicine, memantine significantly slowed the progression of advanced Alzheimer's disease. Patients who took the drug continued to get worse day by day, but their decline was about half as severe as normal.

A separate study found that patients with mild to moderate Alzheimer's disease didn't see any improvement when they added memantine to their current treatments. However, there appears to be a benefit in combining memantine with Aricept (donepezil) since the two drugs regulate different brain functions. In fact, the FDA recently approved this combination for the treatment of moderate to severe Alzheimer's.

How it's taken: Memantine comes in pill form. Doctors usually start with 5 milligrams a day, increasing up to 10 milligrams a day.

Side effects: Headache, dizziness, sedation, agitation, and constipation.

-- Chris Woolston, MS, is a health and medical writer with a master's degree in biology. He is a contributing editor at Consumer Health Interactive, and was a staff writer at Hippocrates, a magazine for physicians. His reporting on occupational health earned him an award from the Northern California chapter of the Society of Professional Journalists.

References

Last updated April 2, 2009
Copyright © 2003 Consumer Health Interactive

or find more on:

Back to top of page