Delirium tremens (often called DTs or "the DTs") is a medical emergency.  It is the worst form of alcohol withdrawal, which can happen when a person who drinks a lot of alcohol suddenly stops drinking. "Delirium" means very bad confusion that comes on quickly; "tremens" means "shaking."

Scientists think the DTs happen because the autonomic nervous system gets too excited.  It works too hard and will not shut off.

DTs were first written about in 1813.

Who gets DTs? 
Most people who stop drinking alcohol do not get the DTs. But some people are more likely to get the DTs if they suddenly stop drinking. DTs are more likely in people who:
 Have had seizures when they tried to stop drinking alcohol before
 Have drunk a lot of alcohol every day for several months
 Have drunk alcohol for more than 10 years
 Are sick or have other medical problems when they suddenly stop drinking

About 5% of people who have alcohol withdrawal symptoms get the DTs. About 5-10% of chronic (long-term) alcoholics get the DTs at some point in their life.

Symptoms 
DTs cause symptoms that can be very bad and very dangerous. Even though not many people get DTs when they stop drinking, many people that do get DTs die from them.  Others get permanent brain damage or other problems.

Symptoms usually start within 2 to 3 days after the person had their last drink.  But in some people, DTs can happen up to a week or 10 days after their last drink.

Life-threatening symptoms 
 
Most people who die from DTs die from one or more of these symptoms:
 Very bad seizures, especially status epilepticus
 Hyperthermia (a very high body temperature; if the body's temperature gets high enough, the brain will die)
 Severe hypertension (very high blood pressure; if the blood pressure gets high enough, it can cause a stroke)
 Severe tachycardia (very high heart rate; if the heart beats too fast, it cannot get blood and oxygen to the rest of the body.  Without enough blood and oxygen, no part of the body can survive.  Eventually breathing can stop. The brain can die or be damaged. The heart can stop beating normally or stop beating completely.)

Other changes to the body 
Other body symptoms caused by DTs include:
 Very bad sweating
 Shaking or tremors (which may be uncontrollable)
 Insomnia (being unable to sleep)
 Feeling very restless 
Anxiety
Anger and irritability

Changes to thinking and feelings 
DTs can cause changes to thinking and feelings that can be very scary for the patient:
 Very bad anxiety, panic attacks, paranoia, or agitation (feeling very upset and unable to relax)
The person may be so anxious or upset that they are certain they are going to die
 Being very confused (for example, the person might not recognize their family members)
 Being disoriented (for example, the person may not know who he is, where he is, or what is happening)
 Being unable to think normally or pay attention to anything
 Being unable to talk normally
Delusional thinking and paranoia
Depression and suicidal thoughts

Changes to the senses 
DTs can cause major changes to the senses, especially what a person sees, hears, and feels.  For example:
 Visual hallucinations: seeing things that are not really there.  These things seem very real to the person with DTs.  For example, sometimes people with DTs see very scary visions of insects, snakes, or rats.
 These visions often go along with the feeling that things like bugs are crawling on the person with DTs.
 Auditory hallucinations: hearing things that are not really there.

Treatment 
DTs always need to be treated in a hospital.  If a person starts having symptoms of DTs at home, 9-1-1 (or their local emergency number) should be called for an ambulance right away.

Several types of medicines can be used to treat DTs:
 Benzodiazepines are the most common type of medicine used for DTs.  In the United Kingdom, chlordiazepoxide (Librium) and diazepam (Valium) are most often used.  In the United States, lorazepam (Ativan) and oxazepam are often used too. These medicines will keep the person asleep or relaxed, make them more comfortable, and help prevent seizures.
 Sometimes anticonvulsant (anti-seizure) medicines are also used to prevent or treat seizures.
 Antipsychotic medicines, like haloperidol (Haldol), may be used to help make hallucinations go away.
People with DTs are also often given thiamine (vitamin B1), an important vitamin, because alcoholics often do not have enough thiamine.  If thiamine levels are low enough, this can cause brain damage.

References

Symptoms
Addiction