How Is Alzheimer's Disease Treated?

Treatment for mild to moderate Alzheimer’s

Treating the symptoms of Alzheimer’s can provide people with comfort, dignity, and independence for a longer period of time and can encourage and assist their caregivers as well. 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.

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, so these medicines may eventually lose their effect. 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.

Medications that target the underlying causes of a disease are called disease-modifying drugs or therapies. Aducanumab is the only disease-modifying medication currently approved to treat Alzheimer’s. This medication is a human antibody, or immunotherapy, that targets the protein beta-amyloid and helps to reduce amyloid plaques, which are brain lesions associated with Alzheimer’s. Clinical studies to determine the effectiveness of aducanumab were conducted only in people with early-stage Alzheimer’s or mild cognitive impairment. Researchers are continuing to study whether this medication works to affect a person’s rate of cognitive decline over time.

Before prescribing aducanumab, doctors may require PET scans or an analysis of cerebrospinal fluid to evaluate whether amyloid deposits are present in the brain. This can help doctors make an accurate diagnosis of Alzheimer’s before prescribing the medication. Once a person is on aducanumab, their doctor or specialist may require routine MRIs to monitor for side effects such as brain swelling or bleeding in the brain.

Several other disease-modifying medications are being tested in people with mild cognitive impairment or early Alzheimer’s as potential treatments.

Treatment for moderate to severe Alzheimer’s

A medication known as 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 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 his or her ability to use the bathroom independently for several more months, a benefit for both the person with Alzheimer's and 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.