Table 1:

Cholinesterase inhibitors and memantine for the treatment of cognitive and neuropsychiatric symptoms in patients with Lewy body dementia

	Dosing	Adverse effects	Comment
Donepezil	5 mg once daily for 4-6 weeks, increased to 10 mg daily if tolerated	Overall cholinesterase inhibitors are well tolerated; adverse effects include: gastrointestinal symptoms, postural hypotension, urinary frequency, drooling, watering eyes, runny nose, and worsening of extrapyramidal motor symptoms, particularly fine tremor; these effects only occurs in a few patients, particularly those with more advanced disease; given the high incidence of autonomic dysfunction (eg, orthostatic hypotension, syncope or presyncope, or cardiac dysrhythmia or conduction disturbances), examination for these must be done before treatment; if the patient has a history of these signs and symptoms, cardiac issues, or autonomic dysfunction, an electrocardiogram might be appropriate and specialist cardiology advice might need to be sought, particularly if a pacemaker is required	Double-blind randomised control trial evidence in both patients with dementia with Lewy bodies and those with Parkinson’s disease dementia support the use of donepezil; meta-analyses suggest a similar effectiveness to rivastigmine14,15
Rivastigmine (oral)	1·5 mg twice daily for 4 weeks, increased to 3 mg twice daily. Dose can be increased up to 6 mg twice daily if tolerated	Similar to donepezil	Double-blind randomised control trial evidence in both patients with dementia with Lewy bodies and those with Parkinson’s disease dementia support the use of rivastigmine;14,15 rivastigmine might be associated with more adverse effects than donepezil14,15
Rivastigmine patch	4·6 mg/24 h for 4 weeks, increased to 13·3 mg/24 h if tolerated	Similar to donepezil	Might have advantages in patients with swallowing difficulties; those who have gastrointestinal side-effects in response to oral agents; those that have compliance issues; or if the patient has a history of a variable response to oral dosing
Galantamine	8 mg/day increased to the initial maintenance dose of 16 mg/day after a minimum of 4-6 weeks; if tolerated after 4 weeks at 16 mg/day, a further dose increase to 24 mg/day of galantamine can be attempted	Similar to donepezil	Open-label trial data only, but galantamine might have positive effects on cognition and neuropsychiatric symptoms14
Memantine	Dosing of memantine should be increased gradually (typically by 5 mg per week) to 20 mg once daily (some patients might prefer divided dosing) over 4 weeks according to tolerance	Side-effects of memantine include gastrointestinal symptoms, confusion, somnolence, hypertension, and dizziness; be cautious when prescribing memantine to individuals with a history of seizures or poor renal function; memantine might enhance the effects of dopaminergics, such as selegiline, and can be toxic when given with, for example, amantadine	In clinical trials memantine was superior to placebo on Global Impression of Change scores, but not on cognitive function or other outcomes, with inconsistent findings reported between patients with dementia with Lewy bodies and those with Parkinson’s disease dementia14,17