What Is Delirium And What Causes It?
4 min

What Is Delirium And What Causes It?

4 min
News Research

Delirium is a neurological condition that is terrifying for both patients and caregivers. It can be caused by illness or certain kinds of drugs. Treating it is critical to patient survival - this is a life-threatening condition.

Delirium is a terrifying condition. It always has been. From the time it was first recorded in medical texts, it has been surrounded by question marks. What is it, really? And what causes it?

One of the reasons delirium has been so sensationalised is because of the way the condition has always scared people. Even patients who suffer from it. In the 18th century in particular, delirium was a favourite malady for characters to suffer from in the Gothic fiction of the time.

Explorers to foreign lands could “catch it.” “Exotic” conditions like malaria can cause it. But so can other diseases and conditions, including sexually transmitted diseases and organ failure.

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While it can be caused by a multitude of precipitants, the condition is simple to describe. Delirium is a temporary state of mental confusion. It is a neurological condition affecting the central nervous system and the brain. It can be caused by illness, surgery, and medications. It can also be caused by withdrawal, particularly from alcohol or other drugs.

Historically, delirium was thought to be caused by everything from evil spirits to the devil. Exorcisms performed by priests were a common "remedy" in the Middle Ages.

As medicine modernised, delirium was first described as “brain fever.” Even still, modern medicine is at a loss to treat this condition.

In a sense, delirium is a “brain fever,” but it is also more than that. Delirium is a malfunction of the brain caused by a chemical or physical malfunctioning of the human body. As a result, the brain cannot process stimuli properly. Common causes of delirium include infections - particularly in the bladder, brain, or chest. They also include fever, dehydration, and major surgery. Liver or kidney problems can cause delirium, as can cessation of drugs like benzodiazepines.

Even more terrifying for both the sufferer and caregiver? It can begin suddenly, startling both observers and those experiencing symptoms. Symptoms can include diminished awareness of surroundings or uncertainty of one’s location. It can also include hallucinations or frightening dreams that continue even upon waking.

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Difficulty talking and drowsiness are also common. Confusion in the evening, rapid mood swings, and insomnia are also frequently described symptoms. Delirium is a condition that is also fairly common in hospitals. Almost 10% of hospitalised patients experience the condition. Elderly people and the terminally-ill are at a particularly high risk.



The actual condition occurs when the normal send and receive functions of the brain become impaired. It can be caused by one factor or a combination of them. A severe or terminal illness can cause it. However, so can other situations.

For example, certain kinds of drugs can cause toxicity in the body. In turn, if there is a failure in liver or kidney function, this toxicity cannot be addressed. Signalling functions in the body begin to send faulty or mixed signals. Low sodium can also cause delirium for the same reason. This is why dehydration is also a trigger.

Delirium is also frequently dismissed or overlooked as a “normal” part of aging. Older people are especially susceptible to drug-induced delirium for several reasons. The first is that the body’s ability to clear drugs from the system decreases with age. Many older patients are also frequently on multiple drugs. There is also some research that shows that neurotransmitters become unbalanced with age. This increases one’s sensitivity to drugs - especially those affecting the central nervous system.



Drug-induced cognitive impairment is one of the most common forms of delirium. There are certain kinds of drugs that are known to cause this side effect.

Benzodiazepines, which include sleeping pills and tranquilisers, have a bad rap and for good reason. An abrupt cessation of such medication can cause delirium. Why? These drugs affect the central nervous system.

Opiates are also known to cause delirium. They act directly on opioid receptors in the brain. This class of drugs can cause not only delirium, but more chronic changes in the brain as seen in dementia. Withdrawal from opiates can also cause delirium.

Tricyclic antidepressants used both in pain management and severe depression can trigger dementia. So can corticosteroids, which are used to treat severe asthma attacks.



Treating delirium is a multi-step process that starts with recognising it in the first place. Delirium caused by either infection or drugs is frequently confused with dementia, particularly in the elderly. There is still no blood test to determine if a patient has delirium. Unlike Alzheimer’s, which causes dementia, a brain scan will not reveal delirium.

While both are conditions that impair cognitive ability, dementia and delirium are not the same. Delirium fluctuates, sometimes dramatically. Dementia is a progressively worsening condition usually caused by age.

Delirium is also a highly dangerous condition because, while it can fluctuate, it can also leave permanent damage. If you suspect someone has delirium, you should obtain medical attention for them immediately. Not only can the event itself be life-threatening, the causes can be as well.

Treating delirium requires identifying the trigger of the condition. That can be hard. However, even if it is medication based, symptoms can persist. These are both the top reasons why the condition is so hard to treat.

Relatives can help by reorienting the patient. Not only will patients be safer, they will have people around them who can help recognise that their terrifying delusions are not real.

Physical restraints should only be used as a last resort. Patients who survive the experience often tell of nightmarish visions. Remember, being tied or restrained is often just as terrifying as the illusions many patients suffer.



If you suspect a family member or friend has delirium, the first step is medical care. Once the individual has been delivered into medical care, it is not over. Further steps will need to be taken to ensure that the patient is well taken care of, safe, and monitored.

Be honest with medical personnel about the individual’s condition, drugs they might have taken, and all medical issues. Also, be as honest as you can with the patient. That includes not indulging in their fantasies or hallucinations. For example, if they think giant spiders are just outside the room, make sure they understand there are none. Do not laugh at the patient. For them, the visions and sensations are “real.”

Remember that if you do not immediately recognise the symptoms, you should not blame yourself. Medical personnel, including trained doctors, often have difficulty.


Written by: Zamnesia
Zamnesia has spent years honing its products, ranges, and knowledge of all things psychedelic. Driven by the spirit of Zammi, Zamnesia strives to bring you accurate, factual, and informative content.

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