Know treatment options for Alzheimer’s disease

Alzheimer’s disease, or AD, is the leading cause of neurodegenerative dementias, affecting many patients as well as families who want the best treatment for their loved ones. Although there is no cure for AD, medications are available to treat symptoms that often manifest.

Cholinesterase inhibitors. 
These are the most commonly prescribed medications and are effective in mild to severe dementia. Typical examples include donepezil, galantamine, and rivastigmine. Although cholinesterase inhibitors do not affect the underlying pathology of AD, patients taking them decline in cognitive function more slowly, have delayed nursing home placement, and live longer than patients who are not taking them.

NMDA receptor antagonists.
Memantine is indicated for patients with moderate to severe dementia. It can be used along with a cholinesterase inhibitor. In clinical trials, memantine has been associated with better global function and cognition.

Monoclonal antibodies.
These are the most recently approved treatments. They target amyloid beta, the underlying abnormal protein in AD. Evidence from the two major studies that led to FDA approval of aducanumab has been mixed. Another monoclonal antibody, lecanemab, won accelerated FDA approval in January 2023. The cost, mixed evidence, and questionable clinical applicability of these studies have led many physicians and patients to be cautious about considering these therapies.

Medications for neuropsychiatric symptoms. Besides memory loss, patients with AD can manifest other neuropsychiatric symptoms. For depression and anxiety, the commonly prescribed antidepressants and anxiolytics (e.g., citalopram, paroxetine, sertraline, duloxetine, venlafaxine) can be beneficial. Any medications that can impair cognition or cause sedation, such as benzodiazepines, should be avoided. Treating psychotic symptoms is challenging because antipsychotic drugs are associated with increased risk of death in elderly patients with dementia, so the risks and benefits should be reviewed with the patient’s physician. Sleep can also be problematic but can be helped by good sleep hygiene and judicious use of hypnotics (e.g., antidepressant-hypnotics, such as mirtazapine and trazodone), while avoiding anticholinergics (e.g., diphenhydramine or tricyclics).

Non-pharmacological therapies. Many clinical studies have demonstrated the benefit of cognitive and physical exercise to slow cognitive decline and improve overall health. The Mediterranean diet and the "MIND" diet, which applies the Mediterranean diet to patients with high blood pressure, may delay onset of AD symptoms and can protect against memory decline. While many have proposed various vitamins and supplements (e.g., gingko biloba, vitamin E) to help with AD, the few large-scale clinical trials conducted have not demonstrated symptomatic benefit.

As with any medical disease, careful consideration of prescribed medications should be discussed with one’s established physician. Dementia can take many forms, and appropriate diagnosis is important, so talking to the primary care doctor and potentially seeking specialty referral — such as to geriatrics, neurology, and psychiatry — may be appropriate.