Alzheimer’s disease is complex, and it is unlikely that any one drug or other intervention will ever successfully treat it in all people living with the disease. Still, in recent years, scientists have made tremendous progress in better understanding Alzheimer’s and in developing and testing new treatments.
Several prescription drugs are approved by the U.S. Food and Drug Administration (FDA) to help manage symptoms in people with Alzheimer’s, and other medications have recently emerged to treat the progression of the disease.
Most FDA-approved drugs work best for people in the early or middle stages of Alzheimer’s. There are currently no known interventions that will cure Alzheimer’s.
Clinical trials on Alzheimer’s disease treatments
Volunteers are needed for clinical trials that are testing ways to treat Alzheimer’s disease. By joining one of these studies, you may help scientists discover new Alzheimer’s treatments and contribute useful information to help people living with Alzheimer’s disease.
Treatment for mild to moderate Alzheimer’s disease
Treating the symptoms of Alzheimer’s can help provide people with comfort, dignity, and independence for a longer period of time and also assist their caregivers. Galantamine, rivastigmine, and donepezil are cholinesterase inhibitors that are prescribed for mild to moderate Alzheimer’s symptoms. These drugs may help reduce or control some cognitive and behavioral symptoms.
Cholinesterase inhibitors prevent the breakdown of acetylcholine, a brain chemical believed to be important for memory and thinking. As Alzheimer’s progresses, the brain produces less acetylcholine and, over time, these medicines eventually lose their effectiveness. Because cholinesterase inhibitors work in a similar way, switching from one to another may not produce significantly different results, but a person living with Alzheimer’s may respond better to one drug versus another.
Lecanemab and aducanumab are immunotherapies with FDA Accelerated Approval to treat early Alzheimer’s. These drugs target the protein beta-amyloid to help reduce amyloid plaques, one of the hallmark brain changes in Alzheimer’s. Clinical studies to determine the effectiveness of lecanemab and aducanumab were conducted only in people with early-stage Alzheimer’s, or mild cognitive impairment due to the disease. Study results showed lecanemab slowed the rate of cognitive decline among study participants over the course of 18 months and reduced the levels of amyloid in the brain. Study results for aducanumab showed a reduction in amyloid buildup in the brain, as well, but uncertainty in the drug’s ability to slow cognitive decline. Further research is in progress to test these drugs’ ability to slow cognitive decline.
To gain full FDA approval, the drug companies must conduct additional studies on the clinical benefits of the medications. Currently, insurance may only cover these medications in specific situations.
Before prescribing these medications, doctors may order PET scans or an analysis of cerebrospinal fluid to evaluate whether amyloid deposits are present in the brain. There are possible side effects to taking these medications, including amyloid-related imaging abnormalities (ARIA), which can lead to fluid buildup or bleeding in the brain. ARIA symptoms are generally mild, but in rare instances they may be serious and life-threatening. Due to this potential risk, monitoring with routine MRIs for side effects related to ARIA is required.
Several other disease-modifying medications are being tested in people with mild cognitive impairment or early Alzheimer’s.
Treatment for moderate to severe Alzheimer’s disease
A medication known as memantine, an N-methyl-D-aspartate (NMDA) antagonist, can be prescribed to treat moderate to severe Alzheimer’s. This drug’s main effect is to decrease symptoms, which could enable some people to maintain certain daily functions a little longer than they would without the medication. For example, memantine may help a person in the later stages of the disease maintain their ability to use the bathroom independently for several more months, a benefit for both people with Alzheimer’s and their caregivers.
Memantine 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 differently from cholinesterase inhibitors, the two types of drugs can be prescribed in combination.
The FDA has also approved donepezil, the rivastigmine patch, and a combination medication of memantine and donepezil for the treatment of moderate to severe Alzheimer’s.
Dosage and side effects of Alzheimer’s disease medications
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 people may benefit from higher doses of Alzheimer’s medications. However, the higher the dose, the more likely unwanted side effects will occur.
Patients should be monitored when a drug is started. All of these medicines have possible side effects that may include nausea, vomiting, diarrhea, allergic reactions, loss of appetite, headaches, confusion, dizziness, and falls. 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. Talk with your doctor before adding or changing any medications.
Alzheimer’s disease treatment medications
The following list provides an overview of Alzheimer’s medications. It’s important to talk with your health care provider about your treatment options and which ones may be most appropriate for you.
FDA-approved medications to treat symptoms
- Donepezil. Cholinesterase inhibitor. Treats mild, moderate, and severe Alzheimer’s by preventing the breakdown of acetylcholine in the brain. Possible side effects include nausea, vomiting, diarrhea, insomnia, muscle cramps, fatigue, and weight loss. Delivered orally once a day through a tablet that is either swallowed or dissolves in the mouth.
- Rivastigmine. Cholinesterase inhibitor. Treats mild, moderate, and severe Alzheimer’s by preventing the breakdown of acetylcholine and butyrylcholine (a chemical similar to acetylcholine) in the brain. Possible side effects include nausea, vomiting, diarrhea, weight loss, indigestion, decreased appetite, anorexia, and muscle weakness. Delivered orally through a capsule twice a day or through a skin patch that is replaced once a day.
- Galantamine. Cholinesterase inhibitor. Treats mild to moderate Alzheimer’s by preventing the breakdown of acetylcholine and stimulates nicotinic receptors to release more acetylcholine in the brain. Possible side effects include nausea, vomiting, diarrhea, decreased appetite, weight loss, dizziness, and headache. Delivered orally through an extended-release capsule, tablet, or liquid. Extended-release capsule is taken once a day. Tablet and oral solution are each taken twice a day.
- Memantine. NMDA antagonist. Treats moderate to severe Alzheimer’s by blocking the toxic effects associated with excess glutamate and regulates glutamate activation. Possible side effects include dizziness, headache, diarrhea, constipation, and confusion. Delivered orally through an extended-release capsule, tablet, or liquid. Extended-release capsule is taken once a day. Tablet and oral solutions are each taken once a day.
- Memantine and Donepezil (manufactured combination). NMDA antagonist. Treats moderate to severe Alzheimer’s by blocking the toxic effects associated with excess glutamate and prevents the breakdown of acetylcholine in the brain. Possible side effects include headache, nausea, vomiting, diarrhea, dizziness, anorexia, and ecchymosis (small bruising from leaking blood vessels). Delivered orally through an extended-release capsule once a day.
Medications with FDA Accelerated Approval to treat the underlying disease
- Aducanumab. Disease-modifying immunotherapy. Treats mild cognitive impairment or mild Alzheimer’s by removing abnormal beta-amyloid to help reduce the number of plaques in the brain. Possible side effects include ARIA, headache, dizziness, falls, diarrhea, and confusion. Delivered through IV over one hour every four weeks.
- Lecanemab. Disease-modifying immunotherapy. Treats mild cognitive impairment or mild Alzheimer’s by removing abnormal beta-amyloid to help reduce the number of plaques in the brain. Possible side effects include ARIA, headache, cough, diarrhea, nausea, vomiting, fever, chills, body aches, fatigue, high blood pressure, low blood pressure, and low oxygen. Delivered through IV over one hour every two weeks.
Managing behavioral symptoms of Alzheimer’s disease
Common behavioral symptoms of Alzheimer’s include sleeplessness, wandering, agitation, anxiety, aggression, restlessness, and depression. Scientists are learning why these symptoms occur and are studying new treatments — drug and non-drug — to manage them. Research has shown that treating behavioral symptoms can make people with Alzheimer’s more comfortable and makes things easier for caregivers.
Experts agree that medicines to treat these behavior problems should be used only after other non-drug strategies have been tried. Learn more about behavioral changes in people with Alzheimer’s disease and ways to cope.
Medicines to be used with caution in people with Alzheimer’s disease
Some medicines, such as sleep aids, anti-anxiety drugs, anticonvulsants, and antipsychotics warrant extra caution for people living with Alzheimer’s. These drugs should only be considered as options after:
- A doctor has explained all the risks and side effects of the medicine
- Other, safer non-drug options have not helped treat the problem
People living with Alzheimer’s and their caregivers must watch closely for side effects from these medications.
Sleep aids are used to help people get to sleep and stay asleep. People with Alzheimer’s should not use these drugs regularly because they make the person more confused and more likely to fall. There are lifestyle changes people can make to improve their sleep. Learn more about getting a good night’s sleep.
Anti-anxiety drugs are used to treat agitation. Certain types of anti-anxiety drugs, like benzodiazepines, can cause sleepiness, dizziness, falls, and confusion. For this reason, doctors recommend they only be used for short periods of time, if at all.
Anticonvulsants are drugs sometimes used to treat severe aggression. Side effects may cause sleepiness, dizziness, mood swings, and confusion.
Antipsychotics are drugs used to treat hallucinations, delusions, and paranoia, and agitation and aggression. Side effects of using these drugs can be serious, including increased risk of death in some older people with dementia. They should only be given to people with Alzheimer’s when the doctor agrees the symptoms are severe.
The future of Alzheimer’s disease treatments
Alzheimer’s researchers continue to explore a variety of innovative approaches to treat symptoms as well as underlying disease processes. In ongoing clinical trials, they are developing and testing several new possible interventions. These include additional immunotherapy and other drug therapies, cognitive training, diet, and physical activity.
For more information about treating Alzheimer’s disease
NIA Alzheimer’s and related Dementias Education and Referral (ADEAR) Center
The NIA ADEAR Center offers information and free print publications about Alzheimer’s and related dementias for families, caregivers, and health professionals. ADEAR Center staff answer telephone, email, and written requests and make referrals to local and national resources.
Explore the Alzheimers.gov website for information and resources on Alzheimer’s and related dementias from across the federal government.
This content is provided by the NIH National Institute on Aging (NIA). NIA scientists and other experts review this content to ensure it is accurate and up to date.
April 01, 2023