Conditions and diseases


Symptoms and causes

Symptoms and causes

What is it?

Delirium is a sudden state of confusion. This confusion is a temporary state. As the physical condition improves, the confusion decreases. The period of confusion can vary from a few hours to a few days, and may even last for a few weeks.


  • Not everything seems to get through in conversations. The patient seems less aware and cannot stay focused.
  • The patient is sometimes restless and cannot sit still. He or she may sweat excessively and suddenly start to tremble.
  • The person’s memory is not functioning well. Something you may have just stated can be forgotten a little later.
  • The patient sees things that are not there. These can be famous people, but also, for example, objects or animals. Also, sometimes he or she does not recognise you or may mistake you for someone else.
  • The patient may become anxious and sometimes react aggressively based on his or her fears.

All these phenomena are not always equally obvious. Especially in the evening and at night, the confusion may increase.

Possible causes

Delirium can have various causes. The most well-known is excessive drinking (withdrawal symptoms).

But someone who never drinks alcohol can also develop delirium. The primary causes include:

  • surgery
  • pulmonary and heart diseases
  • infections
  • metabolism disorders
  • suddenly stopping alcohol, drugs or medications

Concussion, medication, stress, fever and anxiety can all contribute to the onset or worsening of delirium. Older patients are at a greater risk of developing delirium.

Diagnosis and treatment

Diagnosis and treatment

The physician and health professionals try to identify and treat the causes of delirium as soon as possible. Medication is prescribed to decrease the symptoms of delirium. To prevent the patient from falling out of bed or removing infusion tubes, the patient is sometimes restrained (secured). Now and then, the decision must be made to restrain the patient. You can always discuss this with the nurse or physician before or after treatment.

Tips before visiting someone who has delirium

Tips before visiting someone who has delirium
  • If you visit and the patient reacts unusually, tell him or her who you are and why you have come. If necessary, repeat this information.
  • Explain why he or she is in the hospital. For example: ‘Yesterday, you had hip surgery.’
  • Place a calendar in the room. Mention which day and place it is.
  • Use short clear sentences.
  • Ask simple questions. For example: ‘How did you sleep?’
  • It is better for the patient that you do not go along with the delusions or the things that he or she sees or hears that are not actually there. Do not contradict the person, but make it clear that your perception is different. If this has no effect, stop your attempts. Stay calm.
  • Visitors are important, but preferably not too many people at once. Only sit on one side of the bed. This makes it less confusing for the patient. Do not whisper, this could cause suspicion.

All information on this page can also be found in the leaflet below:

Only available in Dutch:

Treatment centres and specialisations

Treatment centres and specialisations

Latest publication date: 15/05/2024
Supervising author: Dr Claeys Isabel