Neurology/Dementia drugs

Dementia drugs

also: donepezil · rivastigmine · galantamine · memantine · acetylcholinesterase inhibitor

Overview

Symptomatic drugs for Alzheimer's — acetylcholinesterase inhibitors (mild–moderate) and memantine (moderate–severe). NOT for vascular dementia.

Mechanism

Acetylcholinesterase inhibitors (donepezil/rivastigmine/galantamine) raise synaptic acetylcholine (the cholinergic deficit of AD). Memantine is an NMDA-receptor antagonist — reduces glutamate excitotoxicity.

Indications

Alzheimer's disease (and Lewy body / Parkinson's dementia for the ChEIs)
Moderate–severe AD (memantine)

The agents

Donepezil / rivastigmine / galantamineAChE inhibitors

oral (rivastigmine also patch)

Mild–moderate AD; cholinergic AEs (GI, bradycardia); donepezil caution in bradycardia/heart block.

MemantineNMDA antagonist

oral

Moderate–severe AD, or add-on; better tolerated.

Adverse effects

Cholinergic effects (nausea, diarrhoea, bradycardia, syncope)common

ChEIs — caution with bradycardia/AV block.

Memantine: dizziness, headachecommon

Cautions & contraindications

ChEIs in significant bradycardia / heart blockall

These drugs for vascular dementiaall

No benefit — only for AD / Lewy body / PD dementia.

Antipsychotics in dementia (esp. Lewy body)all

↑stroke/mortality; severe sensitivity in LBD.

Interactions

ChEIs + rate-limiting drugs (β-blockers, digoxin) → bradycardia

Monitoring & kinetics

Cognition, weight, heart rate

Oral / patch. Specialist-initiated.

Source: NICE NG97 — Dementia · BNF — Dementia