Alzheimer’s Disease Medications

Alzheimer’s Disease Education & Referral (ADEAR) Center

A Service of the National Institute on Aging

National Institutes of Health

U.S. Department of Health and Human Services

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. 

Treating the symptoms of Alzheimer’s 

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 Alzheimer’s

Medications called cholinesterase inhibitors are prescribed for mild to moderate 

Alzheimer’s disease. 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), 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 Alzheimer’s disease, but research 

indicates that they prevent the breakdown of acetylcholine, a brain chemical 

believed to be important for memory and 

thinking. As Alzheimer’s 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 Alzheimer’s patient may 

respond better to one drug than another. 

Treatment for Moderate 

to Severe Alzheimer’s

A medication known as Namenda®

(memantine), an N-methyl D-aspartate 

(NMDA) antagonist, is prescribed to treat 

moderate to severe Alzheimer’s disease. 

This drug’s main effect is to delay progression of some of the symptoms of 

moderate to severe Alzheimer’s. 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 the disease 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 

FACT SHEET

(continued on back)
DRUG NAME DRUG TYPE 

AND USE HOW IT WORKS COMMON SIDE EFFECTS

Namenda®

(memantine)

N-methyl D-aspartate 

(NMDA) antagonist 

prescribed to treat 

symptoms of moderate 

to severe Alzheimer’s

Blocks the toxic effects 

associated with excess 

glutamate and regulates 

glutamate activation

Dizziness, headache, 

constipation, confusion

Razadyne®

(galantamine)

Cholinesterase inhibitor 

prescribed to treat 

symptoms of mild to 

moderate Alzheimer’s

Prevents the breakdown 

of acetylcholine and stimulates nicotinic receptors to 

release more acetylcholine 

in the brain

Nausea, vomiting, 

diarrhea, weight loss, 

loss of appetite

Exelon®

(rivastigmine)

Cholinesterase inhibitor 

prescribed to treat 

symptoms of mild to 

moderate Alzheimer’s

Prevents the breakdown 

of acetylcholine and butyrylcholine (a brain chemical 

similar to acetylcholine) in 

the brain

Nausea, vomiting, 

diarrhea, weight 

loss, loss of appetite, 

muscle weakness

Aricept®

(donepezil)

Cholinesterase inhibitor

prescribed to treat 

symptoms of mild to 

moderate, and moderate 

to severe Alzheimer’s

Prevents the breakdown 

of acetylcholine in the brain

Nausea, vomiting, 

diarrhea

Medications to Treat 

This brief summary does not include all information import

for professional medical advice. Consult the prescribing d

any other medications or supplements. Drugs are listed 

*Available as a generic drug.
MANUFACTURER’S 

RECOMMENDED DOSAGE 

FOR MORE 

INFORMATION 

• Tablet: Initial dose of 5 mg once a day

• May increase dose to 10 mg/day (5 mg twice a 

day), 15 mg/day (5 mg and 10 mg as separate 

doses), and 20 mg/day (10 mg twice a day) at 

minimum 1-week intervals if well tolerated

• Oral solution: same dosage as above

• Extended-release tablet: Initial dose of 7 mg once 

a day; may increase dose to 14 mg/day, 21mg/day, 

and 28 mg/day at minimum 1-week intervals if well 

tolerated 

For current information about this drug’s 

safety and use, visit www.namenda.com. 

Click on “Prescribing Information” to see the 

drug label. 

• Tablet*: Initial dose of 8 mg/day (4 mg twice a day)

• May increase dose to 16 mg/day (8 mg twice a 

day) and 24 mg/day (12 mg twice a day) at 

minimum 4-week intervals if well tolerated

• Oral solution*: same dosage as above

• Extended-release capsule*: same dosage as 

above but taken once a day

For current information about this drug’s 

safety and use, visit www.razadyneer.com. 

Click on “Important Safety Information” to 

see links to prescribing information.

• Capsule*: Initial dose of 3 mg/day (1.5 mg twice 

a day)

• May increase dose to 6 mg/day (3 mg twice a 

day), 9 mg (4.5 mg twice a day), and 12 mg/day 

(6 mg twice a day) at minimum 2-week intervals 

if well tolerated

• Patch: Initial dose of 4.6 mg once a day; may 

increase to 9.5 mg once a day after minimum 

of 4 weeks if well tolerated

• Oral solution: same dosage as capsule

For current information about this drug’s 

safety and use, visit www.fda.gov/cder. 

Click on “Drugs@FDA,” search for Exelon, 

and click on drug-name links to see “Label 

Information.”

• Tablet: Initial dose of 5 mg once a day

• May increase dose to 10 mg/day after 4-6 weeks 

if well tolerated

• Orally disintegrating tablet: same dosage as above

For current information about this drug’s 

safety and use, visit www.fda.gov/cder. 

Click on “Drugs@FDA,” search for Aricept, 

and click on drug-name links to see “Label 

Information.” 

 Alzheimer’s Disease

tant for patient use and should not be used as a substitute 

doctor and read the package insert before using these or 

 in order of FDA approval, starting with the most recent.
NIH Publication No. 08-3431 November 2008 (updated July 2010) 

To learn about support groups, research 

centers, research studies, and publications about Alzheimer’s disease, contact 

the following resources:

Alzheimer’s Disease Education and 

Referral (ADEAR) Center

P.O. Box 8250

Silver Spring, MD 20907-8250

1-800-438-4380 (toll-free)

www.nia.nih.gov/Alzheimers

The National Institute on Aging’s 

ADEAR Center offers information and 

publications for families, caregivers, and 

professionals on Alzheimer’s disease 

research, diagnosis, treatment, patient 

care, caregiver needs, long-term care, 

education, and training. 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 newsletter subscriptions; an 

Alzheimer’s clinical trials database; the 

Alzheimer’s Disease Library database; 

and more. 

Alzheimer’s Association

225 North Michigan Avenue, Floor 17 

Chicago, IL 60601-7633

1-800-272-3900 (toll-free) 

1-866-403-3073 (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 Alzheimer’s, their families, 

and caregivers. The Association also 

supports research on Alzheimer’s.

For More Information

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 

Alzheimer’s disease.

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 Alzheimer’s and the drugs’ possible 

side effects are summarized in the table 

(see inside). 

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.

(continued from front)

Testing New Alzheimer’s Drugs

Clinical trials are the best way to find 

out if promising new treatments are 

safe and effective in humans. Volunteer 

participants are needed for many 

Alzheimer’s trials conducted around the 

United States. To learn more, talk with 

your doctor or visit the ADEAR Center’s 

listing of clinical trials at www.nia.nih.

gov/Alzheimers/ResearchInformation/

Clinical Trials. More information is 

available at www.ClinicalTrials.gov.