Alzheimer's Disease Medications Fact Sheet

Several prescription drugs are currently approved by the U.S. Food and Drug Administration (FDA) to treat people who have been diagnosed with Alzheimer’s disease (AD). Treating the symptoms of AD can provide patients with comfort, dignity, and independence for a longer period of time and can encourage and assist their caregivers as well.

It is important to understand that none of these medications stops the disease itself.

Treatment for Mild to Moderate AD

Medications called cholinesterase inhibitors are prescribed for mild to moderate AD. These drugs may help delay or prevent symptoms from becoming worse for a limited time and may help control some behavioral symptoms. The medications include: Razadyne® (galantamine, formerly known as Reminyl® and now available as a generic drug), Exelon® (rivastigmine), and Aricept® (donepezil). Another drug, Cognex® (tacrine), was the first approved cholinesterase inhibitor but is rarely prescribed today due to safety concerns.

Scientists do not yet fully understand how cholinesterase inhibitors work to treat AD, but research indicates that they prevent the breakdown of acetylcholine, a brain chemical believed to be important for memory and thinking. As AD progresses, the brain produces less and less acetylcholine; therefore, cholinesterase inhibitors may eventually lose their effect.

No published study directly compares these drugs. Because they work in a similar way, switching from one of these drugs to another probably will not produce significantly different results. However, an AD patient may respond better to one drug than another.

Treatment for Moderate to Severe AD

A medication known as Namenda® (memantine), an N-methyl D-aspartate (NMDA) antagonist, is prescribed to treat moderate to severe AD. This drug’s main effect is to delay progression of some of the symptoms of moderate to severe AD. It may allow patients to maintain certain daily functions a little longer than they would without the medication. For example, Namenda® may help a patient in the later stages of AD maintain his or her ability to use the bathroom independently for several more months, a benefit for both patients and caregivers.

Namenda® is believed to work by regulating glutamate, an important brain chemical. When produced in excessive amounts, glutamate may lead to brain cell death. Because NMDA antagonists work very differently from cholinesterase inhibitors, the two types of drugs can be prescribed in combination.

The FDA has also approved Aricept® for the treatment of moderate to severe AD.

Dosage and Side Effects

Doctors usually start patients at low drug doses and gradually increase the dosage based on how well a patient tolerates the drug. There is some evidence that certain patients may benefit from higher doses of the cholinesterase inhibitors. However, the higher the dose, the more likely are side effects. The recommended effective dosages of drugs prescribed to treat the symptoms of AD and the drugs’ possible side effects are summarized in the table (see below).

Patients should be monitored when a drug is started. Report any unusual symptoms to the prescribing doctor right away. It is important to follow the doctor’s instructions when taking any medication, including vitamins and herbal supplements. Also, let the doctor know before adding or changing any medications.

For More Information

To learn about support groups, research centers, research studies, and publications about AD, contact the following resources:

Alzheimer’s Disease Education and Referral (ADEAR) Center
P.O. Box 8250
Silver Spring, MD 20907-8250
800-438-4380 (toll-free)
www.nia.nih.gov/Alzheimers

A service of the National Institute on Aging (NIA), the ADEAR Center offers information and publications for families, caregivers, and professionals on diagnosis, treatment, patient care, caregiver needs, long-term care, education and training, and research related to AD. Staff members answer telephone, email, and written requests and make referrals
to local and national resources. The ADEAR website offers free, online publications in English and Spanish; email alert and online Connections newsletter subscriptions; an AD clinical trials database; the AD Library database; and more.

Alzheimer’s Association
225 North Michigan Avenue, Floor 17
Chicago, IL 60601-7633
800-272-3900 (toll-free)
866-403-3073 (TDD/toll-free)
www.alz.org

The Alzheimer’s Association is a national nonprofit association with a network of local chapters that provide education and support for people diagnosed with AD, their families, and caregivers. The Association also supports research on AD.

Table - Medications to Treat Alzheimer's Disease

Note: This brief summary does not include all information important for patient use and should not be used as a substitute for professional medical advice. Consult the prescribing doctor and read the package insert before using these or any other medications or supplements. Drugs are listed in order of FDA approval, starting with the most recent.

(To view this as one table, please open the PDF version of this publication.)

Alzheimer's Disease Education and Referral (ADEAR) Center
A Service of the National Institute on Aging
National Institutes of Health
U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
November 2008