Late-onset psychosis covers a range of diagnostic possibilities. Both underlying physical and psychiatric disorders may contribute to psychotic experiences. Psychiatrists have expertise in disentangling aetiological factors, assessing risk, and devising appropriate plans of care.

Causes of late-onset psychosis include very late onset schizophrenia-like psychosis (VLSOP), delusional disorder, affective disorder, dementia, and delirium. Early-onset schizophrenia may persist into later life and cause psychotic experiences. Physical factors that might contribute to hallucinations include hearing and visual deficits, medication toxicity, and alcohol.

The clustering of physical and psychosocial stressors in later life makes comprehensive geriatric assessment essential. Psychiatrists often call this holistic assessment ’the biopsychosocial approach’.

The use of the Mental Health Act to sanction involuntary treatment may be required if the risks warrant it.

Medication options for late-onset psychosis are limited by older people’s vulnerability to side effects. Much lower doses of antipsychotic drugs are required than for younger patients. Amisulpride has proven efficacy in VLOSP.