Delirium tremens: symptoms, causes and treatment

Delirium tremens (DTs) is one of the most dangerous complications of alcohol withdrawal. It can develop quickly and without prompt medical care, it can be fatal.

Understanding the symptoms, causes and treatment is crucial for both those affected and for anyone supporting someone through alcohol withdrawal.

What are delirium tremens?

DTs is the most severe and potentially life-threatening form of alcohol withdrawal. It’s a medical emergency that typically happens to people who have been drinking heavily for a long period and then stop or drastically reduce their alcohol intake suddenly.

During long-term, heavy alcohol use, the nervous system adapts to the presence of alcohol, which slows down brain activity. When alcohol is suddenly removed, the brain can become hyperactive or overstimulated, which can trigger DTs.

Although DTs is most commonly associated with alcohol withdrawal, it can also occur with other sedative drugs (such as benzodiazepines or barbiturates) or during severe illness in people with a history of heavy alcohol use.

What are the symptoms of delirium tremens?

DTs usually starts within 24 to 72 hours after the last drink, though in some cases, symptoms may occur later. They tend to peak between 3 and 5 days after withdrawal begins.

DTs is a medical emergency and if someone experiences any of these symptoms, they should seek urgent medical attention as untreated DTs can lead to serious complications or death.

Early symptoms

• Tremors or shaking (often starting in the hands)
• Anxiety and restlessness
• Nausea and vomiting
• Sweating and increased heart rate
• Confusion – a form of delirium specific to alcohol withdrawal that affects thinking, memory, awareness and focus

Severe symptoms

• Visual, auditory or tactile hallucinations
• Severe disorientation and agitation
• High fever
• Seizures
• Rapid heartbeat and high blood pressure

What causes delirium tremens?

DTs is caused by sudden alcohol withdrawal after someone has been drinking heavily for a prolonged time. Heavy drinking is generally defined as drinking more than 35 units a week for women or 50 units a week for men – equating to roughly 15 to20 pints or 25 to30 glasses of wine (Source, 2025).

Over time, alcohol suppresses the brain’s excitatory chemicals (such as glutamate). When you stop drinking abruptly, these chemicals surge and can cause the nervous system to become dangerously overstimulated.

Here’s an analogy to help explain how DTs occurs:

Imagine your brain is a car and alcohol is like a heavy foot on the brake that slows down the brain’s activity. The brain tries to compensate by pressing harder on the accelerator, which increases the activity of certain chemicals in the brain to balance things out. When you suddenly stop drinking (take the foot off the brake), the accelerator is still pressed down hard and the brain can race out of control, leading to the symptoms of DTs.

How is DTs diagnosed?

Only a medical professional can diagnose DTs through a combination of methods and tools, including:

• A full review of your medical and alcohol-use history
• A physical examination and neurological assessment
• The use of standardised withdrawal rating scales such as the Clinical Institute for Withdrawal Assessment for Alcohol Revised Scale (CIWA-Ar)
• Laboratory tests for:
  • Organ function, including liver, kidneys and heart
  • Blood alcohol level
  • Urine drug test
  • Electrolyte levels

Diagnosis and treatment for DTs usually take place in a hospital setting where vital signs and symptoms can be closely monitored.

How are delirium tremens treated?

DTs is a medical emergency and requires immediate hospital care. The goal is to stabilise the person, prevent complications, and support the body through the withdrawal process.

Treatment typically lasts several days and prioritises:

• Sedative medications: usually benzodiazepines to calm the overactive nervous system
• IV fluid and vitamin supplements: including thiamine and magnesium to treat deficiencies and support brain function
• Close monitoring: of heart rate, blood pressure, temperature, and neurological status to prevent seizures and worsening of the condition

While DTs is serious and potentially life-threatening, with early medical interventions, most people fully recover.

Outlook and recovery

Recovery from DTs usually takes about a week but some symptoms, such as fatigue, sleep disturbances, and mood changes can persist for longer. To manage withdrawal safely and effectively and reduce the risk of recurrence, it’s important to seek professional help.

Once the symptoms of alcohol withdrawal, including DTs subside, the underlying causes of alcohol dependence must be addressed to ensure long-term recovery. This may include:

• Professional alcohol detox and rehabilitation
• Psychological therapy and relapse prevention
• Ongoing aftercare and support groups

Getting help and support

If you or someone you know is experiencing severe withdrawal symptoms, call 999 or go to A&E immediately.

Other sources of help include:

• Priory offers free addiction assessments, inpatient detox programmes, and ongoing recovery support
• NHS 111: for urgent medical advice
• FRANK: the national drugs and alcohol helpline (0300 123 6600)
• Alcohol change: information and support for people affected by alcohol misuse

With the right professional care, recovery from alcohol dependence is entirely possible and withdrawal symptoms, including DTs, can be treated effectively. Seeking help is a sign of strength, not weakness, and the first step towards a healthier and more balanced life.