Alcohol withdrawal (also called alcohol withdrawal syndrome) is medical problem. It is a set of symptoms that can happen when a person who has drunk alcohol for a long time stops drinking. It can also happen when a person starts drinking less than they used to.

Alcohol withdrawal can be very dangerous. In the worst cases, it can even kill a person. This is why it is dangerous for people who drink a lot to stop drinking without talking to a doctor first.

Why does withdrawal happen?
Alcohol is a central nervous system depressant. This means that alcohol slows down the activity in some parts of the brain. This can create good feelings, like feeling relaxed and happy.

If a person drinks a lot of alcohol, eventually their body will get used to the alcohol. After a while, the person will need to drink more and more alcohol to feel drunk and to slow down parts of their brain. This is called tolerance.

Once the body is used to having alcohol (and having parts of the brain slowed down), suddenly taking away the alcohol will cause withdrawal symptoms. The central nervous system is used to being slowed down by alcohol. So without alcohol, the central nervous system gets very excited and over-active.

A person who gets tolerant to alcohol, and gets withdrawal symptoms when they stop drinking, is physically dependent on alcohol. This is also called physical addiction.

Who gets alcohol withdrawal?
Not everybody who drinks a lot of alcohol gets withdrawal symptoms when they stop. No one knows why some people get withdrawal symptoms and others do not.

About half of people with alcoholism will get withdrawal symptoms if they drink less than usual. About 5% to 20% of patients withdrawing from alcohol will get the most dangerous form of alcohol withdrawal: delirium tremens.  About 1/3 (one out of three) people who have withdrawal seizures will get delirium tremens.

Symptoms of alcohol withdrawal
Symptoms of alcohol withdrawal are mostly caused by a central nervous system that is over-excited and working too hard.

Everybody has a different set of withdrawal symptoms. Some people have only mild symptoms, like being unable to sleep or feeling anxious. Other people have very bad, life-threatening symptoms, like delirium, hallucinations, very high blood pressures, and very high fevers.

Withdrawal usually begins 6 to 24 hours after a person takes their last drink. Acute withdrawal can last for up to one week.

Diagnosis
To be diagnosed with alcohol withdrawal syndrome, patients must have at least two of these symptoms:.
 Tremors in the hands
 Insomnia (trouble sleeping)
 Nausea or vomiting
 Hallucinations (seeing, hearing, or feeling things that are not really there)
 Anxiety
 Being agitated (unable to sit still)
 Tonic-clonic seizures (seizures where the person is not awake and jerks around)
 Autonomic instability (quickly changing symptoms related to the autonomic nervous system, like high blood pressure and high fevers

How bad are the symptoms?
Many things affect how bad alcohol withdrawal symptoms can be. The most important things are: 
 How much alcohol a person has drunk;
 How long the person has been drinking; and
 Whether the person has had alcohol withdrawal symptoms before

Symptoms are also grouped together and put into categories based on how bad they are:
Alcohol hallucinosis: Patients may see, hear, or feel things that are not there, but have no other symptoms. These hallucinations will stop when alcohol withdrawal is over.
Withdrawal seizures: Seizures happen within 48 hours after the person stops drinking alcohol. A person may have a single generalized tonic-clonic seizure, or a brief episode of multiple seizures. 
Delirium tremens: This is the worst form of alcohol withdrawal, and can kill a person. It usually happens 24 to 72 hours after the person stops drinking alcohol. For more information, see the page on delirium tremens.

Order of symptoms
Every person goes through alcohol withdrawal differently. Even the worst of alcohol withdrawal symptoms can happen as soon as 2 hours after a person stops drinking. Because of this, it is best to talk to a doctor, go into the hospital, or get treatment before a person stops drinking alcohol. In many people, however, symptoms usually happen in this order:

Six to 12 hours after the last drink:
 Shaking (tremor)
 Headache
 Sweating
 Anxiety
 Nausea or vomiting
 Insomnia

Twelve to 24 hours after the last drink:
 Confusion
 Hallucinations
 Tremors
 Agitation (being unable to relax)

24 to 48 hours after the last drink:
 Some alcoholics will have seizures, and may even go into status epilepticus. This can kill a person.
 The person will still have all of the other symptoms they had earlier.

48 hours after the last drink:
Usually, people will start to feel better after 48 hours. But sometimes, after 48 hours, alcohol withdrawal can still get worse and turn into delirium tremens. Delirium tremens can last anywhere from 4 to 12 days.

Post-Acute Withdrawal Syndrome (PAWS)
Acute alcohol withdrawal usually lasts only a week. But many alcoholics have what is called Post-Acute Withdrawal Syndrome (PAWS) (also called "protracted alcohol withdrawal syndrome). This means that some withdrawal symptoms continue beyond the acute withdrawal stage. Some withdrawal symptoms can last for at least a year after a person stops drinking.

Symptoms
Symptoms of post-acute withdrawal syndrome (PAWS) can include:
 Cravings for alcohol (wanting alcohol very, very badly)
 Anhedonia (not being able to enjoy things that a person normally likes)
 Not seeing, hearing, tasting, hearing, or smelling things as well as usual
 Feeling disoriented (meaning a person does not know who they are, where they are, or what is going on)
 Nausea and vomiting
 Headaches

Insomnia is also a common symptom of PAWS. It often keeps happening after acute (immediate) alcohol withdrawal. Research has showed that people with insomnia are more likely to relapse (start using alcohol again). Studies have found that magnesium or trazodone can help treat insomnia in recovering alcoholics.

For some people, the acute phase of alcohol withdrawal can last longer than usual. Protracted (longer than usual) delirium tremens has been reported in medical research, but is not common.

Treatment
People with bad alcohol withdrawal symptoms often need to go into a hospital to make sure they are safe while they are withdrawing from alcohol.

Many different medicines can help with the symptoms of alcohol withdrawal:

Benzodiazepines
Benzodiazepines are the most commonly used medication for the treatment of alcohol withdrawal. They can help decrease alcohol withdrawal symptoms and prevent seizures.

The most commonly used benzodiazepines are long-acting (medications whose effects last a long time), like chlordiazepoxide and diazepam (Valium). These seem to be the best medicines for treating delirium, and do not have to be given as often.

Although benzodiazepines work very well at treating alcohol withdrawal, they should be carefully used. Benzodiazepines should only be used for short periods in alcoholics. This is because alcoholics are more likely to get addicted to benzodiazepines. There is a risk of replacing an alcohol addiction with benzodiazepine dependence or adding another addiction. Also, both alcohol and benzodiazepines are depressants. If a person takes both at the same time, they are more likely to get depression or become suicidal.

Vitamins
Alcoholics often do not have enough of certain vitamins in their bodies. One of these important vitamins is thiamine. If a person does not have enough thiamine in their body, they can get serious health problems and even brain damage.

When a person is going through alcohol withdrawal, the most important vitamins are thiamine and folic acid. If an alcoholic who stops drinking does not have enough of these vitamins, they can get Wernicke syndrome, a very serious brain problem. To keep this from happening, people who have stopped drinking alcohol are often given thiamine and folic acid intravenously (through a needle placed into a vein). They may also be given other vitamins. This can help prevent Wernicke syndrome.

Anticonvulsants
Sometimes, anticonvulsant (anti-seizure) medicines are given to try to prevent seizures.

Some evidence says that topiramate (Topamax), carbamazepine (Tegretol), and other anticonvulsants are helpful in treating alcohol withdrawal; however, research is limited.

Other studies have shown that benzodiazepines work just as well as anticonvulsants.

Other medicines
Clonidine may be used along with benzodiazepines to help some of the symptoms of alcohol withdrawal.

Antipsychotic medicines, such as haloperidol, are sometimes used along with benzodiazepines to control agitation or psychosis. However, antipsychotics have to be used carefully. They can make alcohol withdrawal worse, since they make it more likely for a person to have a seizure.

Prognosis
If alcohol withdrawal is not treated correctly, people can die or have permanent brain damage.

Alcoholics often cannot stop drinking alcohol after their withdrawal symptoms are over. Often, they need support for months or years after withdrawal is over.

Related pages
 Alcoholism
 Delirium tremens

References

Alcohol drinking habits
Diseases
Addiction