A chronic slowly progressive organic mental disorder characterised by progressive loss of memory and cognitive
function, with difficulty in carrying out every day activities.


  • Primary degeneration of the brain
  • Vascular disorders
  • Infections e.g. syphilis, TB, HIV/AIDS, meningitis
  • Metabolic disorders e.g. hypothyroidism
  • Deficiencies of vitamin B12 and B1
  • Brain trauma (chronic subdural haematoma, hydrocephalus)
  • Toxic agents e.g. carbon monoxide, alcohol

Clinical features

  • Impairment of short and long term memory
  • Impaired judgment, poor abstract thinking
  • Language disturbances (aphasia)
  • Personality changes: may become apathetic or withdrawn, may have associated anxiety or depression because of failing memory, may become aggressive
  • Wandering and incontinence in later stages

Differential diagnosis

  • Normal aging
  • Delirium, chronic psychosis, depression


  • Guided by history and clinical picture to establish cause
  • Thorough physical, neurologic and mental state examination
  • Laboratory: thyroid hormones, RPR and vitamin B12 levels, other tests as indicated


  • Where possible, identify and treat the cause
  • Psychosocial interventions:
    • education of family members about the illness and about following a regular routine programme
    • provision of regular orientation information
    • creation of an environment to support activities of daily living
  • Assess for and treat other co-occurring health problems e.g depression, HIV

If restless and agitated

  • Haloperidol 0.5-1 mg every 8 hours with higher dose at night if required
    • Adjust dose according to response and review regularly, monitor for and treat extrapyramidal
      side effects with Benzhexol 2 mg every 12 hours if necessary
  • Avoid Diazepam: it can lead to falls and is often not effective


  • Avoid and treat preventable causes