Subtype-specific efficacy and safety of psychotropic medications across major dementias – a literature review

Introduction

Neuropsychiatric symptoms are among the most clinically consequential manifestations of dementia, contributing substantially to distress, caregiver burden, functional decline, and institutionalization. Yet, psychotropic prescribing in dementia is frequently extrapolated across syndromes despite important biological and phenotypic differences between Alzheimer’s disease (AD), dementia with Lewy bodies/Parkinson’s disease dementia (DLB/PDD), frontotemporal dementia (FTD), and vascular dementia (VaD). These subtypes differ in dominant neurotransmitter deficits, behavioural profiles, psychosis burden, and sensitivity to adverse drug reactions. Consequently, a subtype-specific approach to psychopharmacology may offer a better balance between symptomatic benefit and iatrogenic harm than a uniform “dementia-wide” prescribing strategy.

Aims

This narrative review aimed to synthesize the available evidence on the efficacy and safety of psychotropic medications across major dementia subtypes, with particular emphasis on antipsychotics, antidepressants, and cognitive enhancers with relevant neuropsychiatric effects. A further aim was to identify clinically meaningful differences in tolerability and risk that may support subtype-informed prescribing in routine practice.

Methods

A literature review was developed using randomized controlled trials, systematic reviews, meta-analyses, and major clinical reviews addressing pharmacological treatment of behavioural and psychological symptoms in AD, DLB/PDD, FTD, and VaD. Priority was given to higher-quality evidence reporting either symptom-specific efficacy, global neuropsychiatric outcomes, or clinically relevant safety endpoints, including mortality, cerebrovascular events, extrapyramidal effects, and cognitive worsening. Evidence was interpreted comparatively across dementia subtypes to identify patterns of benefit and harm rather than isolated drug effects alone.

Results

Across dementia subtypes, the evidence base proved markedly uneven. In AD, the most recent randomized evidence supports brexpiprazole for agitation [1], while cholinesterase inhibitors and memantine retain modest benefits on cognition and global outcomes that may secondarily reduce neuropsychiatric burden. However, antipsychotics as a class continue to show only modest efficacy and are constrained by increased risks of mortality and cerebrovascular adverse events [2]. Antidepressant data remain mixed: some analyses suggest benefit for agitation with serotonergic agents such as citalopram or sertraline [3], whereas more recent observational evidence raises concern about faster cognitive decline and dose-related harms in some treated patients. In DLB/PDD, cholinesterase inhibitors show the most consistent benefit for hallucinations, delusions, and overall neuropsychiatric burden, while antipsychotics require exceptional caution because severe neuroleptic sensitivity reactions remain a defining safety issue. In FTD, the evidence is limited but clinically suggestive [4]: trazodone and selected SSRIs may improve disinhibition, compulsive behaviours, irritability, or hyperorality, whereas cholinesterase inhibitors and memantine have not demonstrated reliable benefit and may worsen behaviour in some cases. In VaD, cholinesterase inhibitors provide only slight cognitive benefit [5], and evidence for psychotropic efficacy in broader behavioral syndromes remains sparse and less convincing than in AD.

Conclusions

Current evidence supports a subtype-informed, symptom-targeted model of psychotropic prescribing in dementia. AD has the strongest trial base for pharmacological treatment of agitation, DLB/PDD carries the highest risk of medication-related harm due to antipsychotic sensitivity, FTD remains an area of limited but clinically relevant serotonergic options, and VaD shows only modest responsiveness to available agents. Future research should prioritize subtype-stratified randomized trials, head-to-head comparative studies, and longer-term safety analyses to support more precise and safer prescribing in dementia care.

References

1. Lee D, Slomkowski M, Hefting N, et al. Brexpiprazole for the Treatment of Agitation in Alzheimer Dementia: A Randomized Clinical Trial. JAMA Neurol. 2023;80(12):1307-1316.
2. Schneider LS, Dagerman KS, Insel P. Risk of Death With Atypical Antipsychotic Drug Treatment for Dementia: Meta-analysis of Randomized Placebo-Controlled Trials. JAMA. 2005;294(15):1934-1943.
3. Chen K, Li H, Yang L, Jiang Y, Wang Q, Zhang J, et al. Comparative efficacy and safety of antidepressant therapy for the agitation of dementia: A systematic review and network meta-analysis. Front Aging Neurosci. 2023;15:1103039.
4. Trieu C, Gossink F, Stek ML, Scheltens P, Pijnenburg YAL, Dols A. Effectiveness of Pharmacological Interventions for Symptoms of Behavioral Variant Frontotemporal Dementia: A Systematic Review. Cogn Behav Neurol. 2020;33(1):1-15.
5. Battle CE, Abdul-Rahim AH, Shenkin SD, Hewitt J, Quinn TJ. Cholinesterase inhibitors for vascular dementia and other vascular cognitive impairments: a network meta-analysis. Cochrane Database Syst Rev. 2021;2:CD013306