Visual hallucinations in the elderly: understanding, assessing and responding in Nursing home
📑 Table of contents
- What is a visual hallucination? Definitions and distinctions
- Frequency and impact in Nursing home
- The main causes of visual hallucinations in the elderly
- Dementia with Lewy bodies: the neurological hallucinatory signature
- Medications and hallucinations: the iatrogenic trap
- Delirium and acute confusion: the urgency not to miss
- Charles Bonnet syndrome: seeing without being crazy
- Assessing hallucinations in Nursing home: a 5-step approach
- Responding to hallucinations: practical approaches for the team
- Informing and supporting families
“ There is a child in my room. ” “ Black cats on my bed. ” “ A man standing in the hallway is looking at me. ” These phrases are regularly heard by Nursing home teams. In response, the reactions are often the same: denial (“ there is nothing ”), concern (“ he is delirious ”), or a quick call to the doctor for an antipsychotic prescription. Rarely is there a structured clinical approach seeking to understand why this resident sees what he sees.
Visual hallucinations in the elderly in Nursing homes are, however, a symptom rich in information. Their nature, content, context of appearance, and the resident's reaction often allow for differentiating a chronic neurological cause from a reversible iatrogenic cause, an acute delirium, or an unknown sensory disorder. This distinction is clinically crucial: it conditions the therapeutic response, with major safety stakes in certain pathologies such as dementia with Lewy bodies.
This guide provides you with the tools to observe, assess, and respond to visual hallucinations methodically — without rushing to antipsychotics, and without dangerous minimization either.
1. What is a visual hallucination? Definitions and distinctions
A hallucination is a perception without an object: the brain generates a sensory experience — visual, auditory, olfactory, tactile — without any corresponding external stimulus. The person “ really sees ” something that others do not see: it is not simulation or exaggeration.
It is important to distinguish hallucinations from several neighboring phenomena that resemble them but have different causes and implications. An illusion is a distortion of a real stimulus (taking a hanging coat for a person): it is very common in dementias and confusion states, and does not necessarily mean a true hallucination. An eidetic image is the persistence of a visual image perceived after the stimulus has disappeared, without pathological character. An intrusive memory is a mental image from memory, which the person knows is not real. These distinctions have practical implications for assessment.
Hallucinations can be elementary (lights, shapes, colors without meaning — often of ophthalmological or occipital origin) or complex (people, animals, entire scenes — of more elaborate cortical origin). Complex hallucinations are the most frequent in Nursing homes and the most clinically informative.
💡 Hallucination vs illusion: a practical distinction. In a Nursing home, it is common for a resident to confuse a coat hanging on the door for an intruder, or the folds of a curtain for a face. These are illusions — misinterpretations of a real stimulus. They indicate a perceptual disorder or a cortical processing deficit, but are less diagnostically specific than true hallucinations. An attentive caregiver can often resolve them simply by turning on the light or showing the real object to the resident.
2. Frequency and impact in Nursing homes
Visual hallucinations are a common symptom in Nursing homes, under-reported and under-evaluated. Studies estimate their prevalence at 15 to 30% of demented residents, with significant variations depending on the type of dementia: 60 to 70% in DLB, 20 to 30% in moderate to severe Alzheimer's, 10 to 15% in vascular dementia, and episodically in many other pathologies.
The under-reporting is massive for several reasons. Many residents, aware that their visions seem abnormal, do not report them spontaneously for fear of being judged "crazy". Others no longer have the verbal ability to describe them. And some caregivers minimize reports of hallucinations by attributing them to dementia in general, without seeking to analyze them more finely.
The impact of hallucinations on quality of life is variable. Some hallucinations are neutral or even pleasant for the resident — who cohabits peacefully with their "visitors". Others are a source of intense anxiety, agitation, insomnia, and refusal of care. It is the emotional tone of the hallucinations, much more than their mere presence, that determines the level of urgency of the clinical response.
3. Major causes of visual hallucinations in the elderly
Visual hallucinations in the elderly in Nursing homes are not all the same nor all of neurological origin. Several major categories of causes must be systematically considered during evaluation.
| Cause | Mechanism | Characteristics of hallucinations | Urgency |
|---|---|---|---|
| Lewy body dementia (DLB) | Dysfunction of cortical visual pathways (occipital Lewy bodies) | Complex, recurrent, early, low anxiety, people or animals | Moderate — chronic |
| Alzheimer's disease | Involvement of associative visual cortices in moderate to severe stages | Variable, often linked to the emotional content of the moment | Low if not anxiety-inducing |
| Medications (iatrogenesis) | Anticholinergic, dopaminergic, or sedative effects | Appearance after the introduction of a medication, often concerning | High — reversible |
| Delirium (acute confusion) | Acute brain dysfunction (infection, dehydration, pain…) | Sudden onset, fluctuating, associated with confusion and agitation | Very high — emergency |
| Charles Bonnet syndrome | Visual sensory deprivation (AMD, severe cataract) | Complex, elaborate, preserved critical awareness, non-anxiety-inducing | Low — benign |
| Psychiatric disorder | Late-onset psychosis, psychotic depression | Often persecutory, associated with coherent delusional themes | Moderate — psychiatric consultation |
| Temporal/occipital epilepsy | Epileptic discharges from visual cortices | Brief, stereotyped, elementary (lights, shapes), repetitive | High — neurological assessment |
4. DLB: the neurological hallucinatory signature
In Lewy body dementia, visual hallucinations have a very characteristic clinical signature that distinguishes them from all other causes. Recognizing them allows for guiding the diagnosis and immediately adopting the necessary medication precautions.
Distinctive characteristics of DLB hallucinations
DLB hallucinations are complex and detailed: the resident sees whole people, animals, children, sometimes moving scenes. They describe them with precision and coherence ("it's an old man in a gray suit, he is sitting in the armchair"). They are recurrent and stereotyped: the same characters return, in the same places, at similar times. They are early in the progression of the disease, sometimes before any notable cognitive decline. And they are often low anxiety-inducing: the resident can describe them calmly, sometimes with humor ("the gentleman is still there"), maintaining a certain critical distance.
The partial critical awareness is an important element: many DLB patients know that others do not see what they see, even if they cannot help but see it. This partial detachment distinguishes DLB hallucinations from hallucinations of psychosis or delirium, where the conviction of reality is total.
The neurological mechanism
Visual hallucinations in DLB are generated by Lewy bodies in the associative occipital and parietal visual cortices. These regions, normally responsible for interpreting and recognizing visual objects, spontaneously generate complex visual percepts in the absence of stimuli. It is a phenomenon analogous to a "background noise" in the visual circuits — the brain "invents" images because its visual processing circuits are functioning abnormally.
This mechanical understanding is liberating for caregivers and families: DLB hallucinations are not a sign of "madness", not a reaction to a traumatic situation, not a psychiatric delirium. They are neurological artifacts — bothersome but biologically explainable.
« Mrs. Tissot told me this morning that there were three little girls playing in her room. She asked me with a smile if they were coming to see me too. She knew they weren't. She said to me 'it's my illness, I know'. I found that both sad and beautiful. »
5. Medications and hallucinations: the iatrogenic trap
The drug-related cause of visual hallucinations is probably the most underdiagnosed in nursing homes — and yet one of the most easily reversible. Many classes of medications commonly prescribed for elderly people can trigger or worsen visual hallucinations.
The most involved medications
Anticholinergic medications are the first class to monitor : oxybutynin (Ditropan), certain antihistamines, tricyclic antidepressants, certain antiemetics. By blocking central muscarinic receptors, they disrupt the circuits regulating consciousness and perception, potentially triggering hallucinations, especially at night.
Dopaminergic medications for Parkinson's (L-Dopa, dopaminergic agonists like pramipexole or ropinirole) are frequently associated with visual hallucinations, especially in cases of high doses or rapid introduction. In the context of a PSP or a MCI, this risk is further increased by the vulnerability of subcortical dopaminergic circuits.
Corticosteroids at high doses and opioids can also trigger hallucinations, as can benzodiazepines during abrupt withdrawal. Antibiotics from the quinolone family (ciprofloxacin, levofloxacin), often prescribed for frequent urinary infections in nursing homes, are an underrecognized cause of confusion and hallucinations in fragile elderly people.
The sign of chronology
The golden rule for suspecting a drug-related cause is chronology : hallucinations that appear within days or weeks following the introduction or increase of a medication should always suggest an iatrogenic cause. Documenting the date of introduction of each new medication in the care record is a simple gesture that can prevent a cascade of unnecessary prescriptions.
A resident develops hallucinations after the introduction of an anticholinergic medication for urinary incontinence. The on-call doctor, unaware of the recent treatment, prescribes an antipsychotic for the hallucinations. The antipsychotic worsens confusion and hallucinations (especially if MCI). A new molecule is added. The vicious circle is set in motion.
In the face of new hallucinations, first look for a medication-related cause: review the list of treatments, check recent introductions, alert the coordinating physician with the precise chronology. Stopping or substituting the suspected medication is often sufficient to make the hallucinations disappear without resorting to antipsychotics.
6. Delirium and acute confusion: the emergency not to be missed
Delirium — also called acute confusional syndrome or acute confusional state — is a medical emergency that can include visual hallucinations in its clinical picture. Recognizing it quickly is vital because its underlying causes (infection, dehydration, pain, intestinal obstruction, Stroke) require immediate treatment.
The distinctive signs of delirium
Delirium is distinguished from chronic neurological hallucinations by several characteristics. It has a sudden or subacute onset (from a few hours to a few days), often without a hallucinatory history in this resident. It is accompanied by a global alteration of consciousness — very fluctuating attention, major disorientation, incoherence of thoughts. The hallucinations are anxiety-provoking and persecutory, often associated with intense agitation. There is an identifiable underlying cause in the vast majority of cases.
The CAM confusion score (Confusion Assessment Method) is a simple and validated tool that nursing home teams can use to identify delirium. It is based on four criteria: acute onset and fluctuation, inattention, disorganized thinking, and altered level of consciousness. The presence of the first two criteria plus one of the last two indicates a probable delirium.
The causes to look for urgently
In the face of delirium with hallucinations, the causes to look for immediately are: an infection (urinary, pulmonary, skin — the most frequent), dehydration, unexpressed pain (unknown fracture, urinary retention, fecal impaction), a metabolic disturbance (hypoglycemia, hyponatremia, hypercalcemia), an iatrogenic cause (new medication, drug interaction), an acute neurological event (Stroke, epilepsy).
- Temperature and blood pressure — rule out an infection or hemodynamic disturbance
- Capillary blood glucose — eliminate hypoglycemia in a few seconds
- Urine dipstick — screen for a urinary infection, a common cause of delirium
- Hydration status — check the urine output of the last 24 hours, dry mucous membranes
- Pain assessment — look for unexpressed pain (grimaces, pain-relieving positions)
- Review of recent treatments — look for a recent introduction or a change in dosage
- Immediate medical alert — always inform the physician without delay
7. Charles Bonnet syndrome: seeing without being crazy
Charles Bonnet syndrome (CBS) is a common, benign, and extremely underrecognized cause of visual hallucinations in nursing homes. It affects people with severe visual impairment — AMD, advanced glaucoma, severe untreated cataract, diabetic retinopathy — and manifests as complex visual hallucinations in individuals whose cognition and mental state are normal.
Mechanism and presentation
CBS is related to a phenomenon of sensory deprivation: when the brain receives less visual information due to a deficiency in the sensory organ, the visual cortices, deprived of their usual "nourishment," spontaneously generate replacement images. It is somewhat the visual equivalent of tinnitus — a "noise" generated by an insufficiently stimulated sensory system.
The hallucinations of CBS are characteristically elaborate and colorful: costumed characters, blooming gardens, animals, complex architectures. The resident knows they are not real — critical insight is intact — and speaks about them with a mix of astonishment and perplexity. They are not anxiety-provoking and often disappear when the person blinks or moves to a brighter place.
Why it is often confused with early dementia
Families and sometimes caregivers who learn that a resident sees imaginary people may mistakenly conclude that it is early dementia or psychosis. If the resident does not dare to report their hallucinations for fear of this judgment, they remain silent for months or years. CBS is a benign and treatable cause (improvement of visual correction, cataract surgery if possible, optimal lighting) that does not justify antipsychotics or psychiatric hospitalization.
💡 A simple question that makes a difference. Systematically asking the question “ Do you ever see things that others do not see ? ” during the initial assessment or during regular evaluations helps to detect the SCB and DCL hallucinations long before they become anxiety-provoking or sources of agitation. This simple question, integrated into the initial data collection, can change the diagnosis and care plan.
8. Assessing hallucinations in Nursing home: a 5-step approach
When faced with a resident who reports visual hallucinations, or whose behaviors suggest unusual perceptions, a structured approach in five steps allows for quick orientation towards the correct cause and response.
- Accurately describe the hallucinations. Since when ? At what time (day, night, upon waking) ? What content (people, animals, shapes, colors) ? What is the resident's reaction (calm, anxious, agitated) ? Does the resident think it is real or do they have partial awareness ? This information is recorded in the file with time and context.
- Look for an acute onset or recent triggering factor. Sudden onset = delirium to be urgently ruled out. Appearance after a new medication = iatrogenic cause to explore. Hallucinations present for a long time and stable = likely chronic cause (DCL, Alzheimer's, SCB).
- Check basic vital and biological parameters. Temperature, blood pressure, blood sugar, diuresis, urine strip. These simple checks quickly rule out acute medical causes.
- Systematic medication review. List all current medications with their introduction date. Identify molecules with anticholinergic, dopaminergic, sedative effects. Report to the coordinating physician any temporal correlation between medication introduction and the appearance of hallucinations.
- Assess visual acuity and field. Severe uncorrected visual deficit points towards Charles Bonnet syndrome. Check if the resident is wearing their glasses, if their correction is up to date, if a known cataract has been treated.
9. Responding to Hallucinations: Practical Approaches for the Team
Responding to hallucinations depends entirely on their identified cause. There is no universal strategy: what is suitable for benign hallucinations of a DCL is unsuitable for delirium, and vice versa.
For Chronic Neurological Hallucinations (DCL, Alzheimer's disease)
Validation without confirmation is the reference approach. It consists of recognizing the emotional experience of the resident without engaging in the content of the hallucination: “I see that you perceive something. Does this worry you?” This approach reduces anxiety without creating additional confusion about reality.
Environmental adaptation reduces the frequency of hallucinations: uniform lighting without shadow areas (dark areas promote hallucinations), covered mirrors if the resident does not recognize themselves, a decluttered environment without objects that could be misidentified, maintaining soft night lighting (night light). These simple adjustments sometimes significantly reduce the frequency of episodes.
Reorientation through distraction — offering an activity, a change of space, music — can interrupt an anxiety-provoking hallucinatory episode without the need to argue about the reality of the visions.
For Delirium with Hallucinations
Delirium with hallucinations is a medical emergency whose treatment addresses the underlying cause. While awaiting medical intervention, the team ensures the physical safety of the resident (risk of falls, self-harm), maintains a reassuring and calm presence, reduces sensory stimulation (soft light, calm, one caregiver at a time), and avoids any confrontation regarding reality. Non-pharmacological interventions are prioritized; antipsychotics are only used as a last resort and on medical prescription, except for DCL residents where they are contraindicated.
For Charles Bonnet Syndrome
The main approach is psychoeducation: explaining to the resident and the family what CBS is, reassuring them about the benignity of the phenomenon, normalizing the experience by giving it a name (“What you see is called Charles Bonnet syndrome — it’s your brain creating images to compensate for your visual deficit”). Optimizing visual correction (appropriate glasses, high contrast, optimal lighting) reduces the frequency of episodes. No antipsychotic is indicated.
📋 Tableau récapitulatif : répondre selon la cause
- DCL — hallucinations chroniques calmes : validation sans confirmation, adaptation de l'environnement, distraction — jamais de neuroleptiques
- Alzheimer — hallucinations épisodiques : validation, réorientation, adapter si anxiogènes — antipsychotiques en dernier recours
- Iatrogènes — médicament suspect : alerter le médecin pour réévaluation du traitement — souvent réversible sans ajout de médicament
- Delirium — début brutal + agitation : urgence médicale — traiter la cause — sécuriser l'environnement
- Charles Bonnet — déficit visuel + insight : psychoéducation, optimisation visuelle — aucun antipsychotique
10. Informer et soutenir les familles
Pour les familles, découvrir que leur proche voit des personnes ou des animaux inexistants est souvent terrifiant. La réaction la plus fréquente est la conviction que la démence « empire » brutalement, ou — plus rarement — le doute sur la réalité des visions (« peut-être qu'il y a vraiment quelque chose que nous ne voyons pas »). L'équipe a un rôle pédagogique essentiel pour transformer cette terreur en compréhension.
L'explication neurologique — simple, concrète, dépourvue de jargon technique — rassure la plupart des familles. Expliquer que les hallucinations sont générées par des circuits cérébraux dysfonctionnels, comme un « court-circuit visuel », et non par une folie progressive ou une décompensation psychiatrique, change radicalement le regard de la famille sur le symptôme.
Montrer aux familles comment répondre concrètement lors d'un épisode — ne pas confronter, ne pas entrer dans le délire, accueillir avec empathie, proposer une distraction — leur donne un rôle actif et les soulage de l'impuissance. Une fiche pratique simple (« Que faire quand il/elle voit des personnages ? »), remise à la famille dès l'apparition des premiers épisodes, est un outil précieux qui se rédige en quelques minutes et peut transformer des visites anxiogènes en moments de connexion bienveillante.
M. Picard, résident Alzheimer modéré stable depuis 2 ans, présente brutalement en 48 heures des hallucinations visuelles intenses (il voit des insectes sur les murs et son lit), une agitation importante et un refus alimentaire. Il n'avait jamais présenté d'hallucinations auparavant. L'infirmière de nuit note le comportement et le signale dans les transmissions. Une aide-soignante remarque qu'une infection urinaire a été traitée par ciprofloxacine 3 jours plus tôt.
L'infirmière coordinatrice alerte le médecin coordonnateur qui identifie la ciprofloxacine comme cause probable (quinolone connue pour ses effets neuropsychiatriques). L'antibiotique est changé pour l'amoxicilline. L'état de M. Picard s'améliore en 48 heures.
✅ Résultat : Les hallucinations disparaissent complètement en 4 jours après le changement d'antibiotique. Aucun antipsychotique n'a été prescrit. La vigilance de l'équipe soignante et la traçabilité de l'introduction médicamenteuse ont évité une cascade de prescriptions inutiles.
Mme Giraud, 87 ans, sans antécédent de démence, signale depuis 3 mois voir des papillons colorés et des enfants en costume qui dansent dans sa chambre. Elle précise en souriant qu'elle sait que « c'est dans sa tête » mais que c'est très beau. Sa fille, alertée, pense à une démence débutante. Le médecin coordonnateur est consulté et réalise un bilan ophtalmologique : DMLA bilatérale sévère avec acuité visuelle très réduite.
Le diagnostic de syndrome de Charles Bonnet est posé. La fille et la résidente reçoivent une explication complète sur le mécanisme et le caractère bénin du phénomène. L'éclairage de la chambre est optimisé. La résidente est rassurée et rapporte que ses visions sont moins fréquentes depuis qu'elle sait ce que c'est.
✅ Résultat : Aucun antipsychotique prescrit. La fille, rassurée, ne vit plus les visites avec anxiété. Mme Giraud dit qu'elle trouve ses papillons « moins envahissants depuis qu'ils ont un nom ». Une consultation ophtalmologique pour injection anti-VEGF est programmée.
🤝 Les 10 réflexes de l'équipe face aux hallucinations visuelles
- Décrire précisément l'hallucination dans le dossier (contenu, heure, contexte, réaction du résident)
- Chercher un début aigu — si oui, traiter comme urgence médicale
- Vérifier la liste des médicaments introduits dans les 2 semaines précédentes
- Mesurer les paramètres vitaux et glycémie capillaire systématiquement
- Vérifier l'acuité visuelle et le port des lunettes (Charles Bonnet)
- Ne jamais confirmer ni dénier les hallucinations — approche par validation
- Ne jamais précipiter la prescription d'antipsychotiques sans diagnostic étiologique
- Ne jamais donner de neuroleptiques classiques sans vérifier l'absence de DCL
- Adapter l'environnement (lumière, miroirs, stimulation visuelle)
- Former la famille à la réponse adaptée lors des visites
Les hallucinations visuelles ne sont pas une fatalité mystérieuse inhérente à la vieillesse. Ce sont des symptômes neurologiques, médicamenteux ou sensoriels qui ont des causes identifiables et des réponses adaptées. Une équipe EHPAD formée à les analyser méthodiquement — plutôt qu'à y répondre par réflexe ou par défaut — offre à ses résidents une prise en charge plus sûre, plus humaniste et souvent plus efficace.
🎓 Formez votre équipe à l'évaluation des hallucinations visuelles
La formation DYNSEO sur les maladies apparentées à Alzheimer couvre les hallucinations visuelles dans toutes leurs causes : DCL, iatrogénie, delirium, Charles Bonnet. Approche clinique et réponse pratique pour toute l'équipe EHPAD. Certifié Qualiopi.