Pharmacological therapy for cognitive impairment in Alzheimer dementia

Drug treatments for Alzheimer dementia are not curative and do not modify disease progression.

Acetylcholinesterase inhibitors are the drug class of choice for Alzheimer dementia; in the short term, they modestly improve or stabilise cognition, alertness and function. All acetylcholinesterase inhibitors appear to have similar efficacy for Alzheimer dementia. Their modest benefits must be weighed against their significant adverse effects, which include prominent gastrointestinal adverse effects (particularly nausea, vomiting and anorexia), weight loss, vivid dreams, urinary incontinence, tremor, cramps, bradycardia, dizziness and drowsiness. Because of these adverse effects, the benefit–harm profile of acetylcholinesterase inhibitors varies depending on patient factors. Before starting an acetylcholinesterase inhibitor, perform an electrocardiogram (ECG), record the patient’s weight and assess their falls risk. Most adverse effects are dose-related; the regimens below aim to minimise adverse effects by starting treatment with a low dose and slowly increasing.

Donepezil, galantamine and the rivastigmine transdermal patch are easier to use than oral rivastigmine because they are dosed once daily and the dose can be more easily titrated. The rivastigmine transdermal patch is better tolerated than the oral formulation.

Memantine offers a small, short-term improvement or stabilisation in cognition and function for people with moderate to severe Alzheimer dementia (regardless of whether it is given as monotherapy or in combination with an acetylcholinesterase inhibitor).

Before starting pharmacological therapy for cognitive impairment in Alzheimer dementia, discuss potential benefits and harms with the patient or their substitute decision maker—consider their goals of care and create a plan for when to stop therapy; see Modification and duration of pharmacological therapy for cognitive impairment in dementia.

If an acetylcholinesterase inhibitor is considered appropriate to treat cognitive symptoms of Alzheimer dementia and the patient has undergone an ECG, a falls risk assessment and had their baseline weight recorded, use:

If memantine is considered appropriate to treat cognitive impairment in a patient with moderate to severe Alzheimer dementia (eg a patient who cannot take an acetylcholinesterase inhibitor), use: