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By Medicover Hospitals / 10 Mar 2021
Home | symptoms | delirium
  • Severe disturbance of mental abilities results in confused thinking and reduced awareness of the environment. Delirium is also called a confused mental state or sudden confusion. Delirium can have causes that are not due to an underlying disease. Examples include intoxication or sleep deprivation.
  • Article Context:

    1. What is Delirium?
    2. Types of Delirium
    3. Causes
    4. Diagnosis
    5. Treatment
    6. When to visit a Doctor?
    7. Prevention
    8. FAQ's

    What is Delirium?

  • Delirium refers to a state of severe confusion and rapid changes in brain function that occur suddenly. It is related to hallucinations and hyperactivity, and the victim is inaccessible to normal contact. Delirium can occur because of a wide variety of causes, including head trauma, drug use or withdrawal, poisoning, brain tumors, infections, and metabolic disorders. A urinary tract infection or pneumonia, for example, can lead to delirium in older people. The prognosis for delirium depends on the underlying cause of the disease. Delirium can also occur because of mental illness. Signs may include changes in alertness or level of consciousness, confusion, drowsiness, incontinence, delusions, changes in speech, emotional changes, reduced memory, problems concentrating, disorientation, disorganized thinking, and changes in perception.
  • Types of Delirium:

    • The two types of delirium are:
      • Hyperactive delirium: The person becomes hyperactive (agitated or agitated).
      • Hypoactive delirium: The person is underactive (drowsy and slow to respond).
    • Hypoactive delirium is more common and affects up to 75% of people with delirium. But many people, including health care providers, may mistakenly assume that the person is depressed.
    • People can experience both types of delusions together. They can be extremely alert one minute and drowsy the next.


  • Delirium occurs when the normal sending and receiving of signals in the brain are impaired. This impairment is probably caused by a combination of factors that make the brain vulnerable and trigger brain activity dysfunction.
  • Delirium can have a single cause or more than one cause, such as a combination of a medical condition and drug toxicity. Sometimes no cause can be identified. Possible causes include:
    • Certain medications or drug toxicity
    • Alcohol or drug intoxication or withdrawal
    • A medical condition, such as a stroke, heart attack, worsening of lung or liver disease, or injury from a fall
    • Metabolic imbalances, such as low sodium or calcium
    • Serious, chronic, or terminal illness
    • Fever and acute infection, especially in children
    • Urinary tract infection, pneumonia, or the flu, especially in the elderly
    • Exposure to a toxin, such as carbon monoxide, cyanide, or other poisons
    • Malnutrition or dehydration
    • Sleep deprivation or severe emotional distress
    • Pain
    • Surgery or other medical procedures that include anesthesia
  • Several drugs or drug combinations can trigger delirium, including some types of:
    • Pain medication
    • Sleep medications
    • Medicines for mood disorders, such as anxiety and depression
    • Allergy medications (antihistamines)
    • Asthma medication
    • Steroid drugs called corticosteroids
    • Medicines for Parkinson's disease
    • Medicines to treat spasms or convulsions


  • The diagnosis of delirium begins with a review of the patient's medical history. Next, the doctor is likely to assess the mental state of the patient by looking for awareness, attention, and reflection. These assessments can be done informally through conversations.
  • The doctor may also wish to perform physical and neurological examinations. These exams look for any underlying health problems or diseases that could cause delirium.
  • Treatment:

  • If a person unexpectedly develops confusion, urgent medical attention should be sought. Often, the patient is so confused to inform doctors of their condition, and the history is often taken from a family member or someone who knows the patient well.
  • Treatment aims to correct the underlying cause. For example, the infection would be treated with antibiotics.
  • Sedatives can make delirium worse and should only be given where:
    • Patients are extremely anxious
    • The patient has suddenly withdrawn from alcohol or drugs
    • When the patient risks endangering himself or others
    • To calm someone down enough to receive treatment

    When to visit a Doctor?

  • See a doctor immediately if you or someone else suddenly:
    • Sees or hears things that others do not see
  • Gets confused and doesn't know where they are
  • No longer recognize the people around them


  • Treating the conditions that cause delirium can lower its risk. In hospitalized people, avoiding or using a less dosage of sedatives, prompt treatment of metabolic condition and infections, and using reality counseling programs will reduce the risk of delirium in those at high risk.
  • Frequently Asked Questions:

  • Delirium usually improves when the cause is treated. You can make a quick recovery, but it can sometimes take days or even weeks and leave memories alive. A man who became delusional at sea was rescued and his hypothermia was successfully treated.
  • Delirium can last for a few days, weeks, or even months, but people with dementia may take longer to recover. In hospitals, about 20-30% of older people in medical services will suffer from delirium and up to 50% of people with dementia.
  • Delirium can be triggered by a serious medical illness such as infection, certain medications, and other causes, such as drug withdrawal or intoxication. Older patients, over 65, are most at risk of developing delirium. People with a history of brain disease or brain damage are also at risk.
  • Citations:

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