Mental confusion

Clinical features

The clinical picture includes:
– disorientation in time and space;
– impaired consciousness;
– concentration problems;
– memory impairment.
These symptoms develop rapidly (hours or days), and often fluctuate during the course of the day.
Agitation, delusions, behavioural disorders and hallucinations (often visual) may complicate the picture.


Mental confusion almost always has an organic cause:
– Infectious: meningitis, cerebral malaria, encephalitis, septicaemia, syphilis, AIDS, etc.
– Metabolic: hyper/hypoglycaemia, electrolyte imbalance, niacin or B1 deficiencies, etc.
– Endocrine: thyroid disorders
– Neurological: epilepsy, raised intracranial pressure, head trauma, meningeal haemorrhage, brain tumour, etc.
Also consider the use of drugs which may cause mental confusion (opioid analgesics, psychotropic drugs, fluoroquinolones, etc.), use of toxic substances (alcohol/drugs), or withdrawal from these substances.

Mental confusion requires hospitalisation. Treat the underlying cause.

In case of agitation, the administration of diazepam may increase mental confusion. 
If it is absolutely necessary to sedate the patient, use a low dose of risperidone PO (one dose of 2 mg) or haloperidol IM (one dose of 2.5 mg).

In case of mental confusion related to stopping alcohol (delirium tremens):
– Admit the patient to an intensive care unit.
– Administer diazepam IV: 10 to 20 mg 4 to 6 times daily, under close supervision with ventilation equipment near at hand. The goal is to achieve mild sedation without provoking respiratory depression. The doses and duration of the treatment are adapted according to the clinical progress.
– Add chlorpromazine IM if necessary: 25 to 50 mg 1 to 3 times daily.
– IV hydration: 2 to 4 litres 0.9% sodium chloride per 24 hours.
– Administer thiamine IM: 100 mg daily for at least 3 days.
– Monitor vital signs and blood glucose levels.