Abstinência aguda de álcool e delirium tremens

This article focuses specifically on acute alcohol withdrawal and delirium tremens. The National Institute for Health and Care Excellence (NICE) has developed guidelines for the clinical management of alcohol use disorders and this article is based on these.¹²³

See related separate articles Alcoolismo e uso indevido de álcool - reconhecimento e avaliação, Alcoholism and alcohol dependence - management e Alcohol-related problems.

Epidemiologia⁴

In England in 2022, 56% of adults report drinking alcohol weekly (61% of men and 51% of women). 32% of men exceed the recommended weekly amount compared with 15% of women. The mean number of units consumed by all adults in England per week was 13.3⁵About 20% of people in the UK report drinking no alcohol.⁵

Alcohol use changed during the COVID pandemic with heavy drinkers tending to drink more and lighter drinkers tending to drink less.²⁶

Alcohol drinking at hazardous, harmful or dependent levels can be characterised as Alcohol Use Disorder (AUD).

• 18% of adults in England drink at hazardous levels (AUDIT score of 8+) with 1.8% drinking harmful levels and 0.9% affected by alcohol dependence.

• Men are more likely to drink at hazardous levels or above than women.

• Drinking at hazardous levels or above has fallen from 26% in 2000 to 18% in 2024.

• Drinking at hazardous levels fell the most amongst people aged 16-24 (40% to 18%), and also reduced in 24-44 year olds. The numbers drinking at hazardous levels was stable in people between 45 and 74 and increased in those aged over 75 (6% to 10%)

• Having a common mental health condition (depression or anxiety)⁷ is related to increased risks of hazardous drinking. 3% of adults with a common mental health condition drink at harmful levels and 2.3% have probable alcohol dependence, compared with 1.4% and 0.6% of the general population.

• Higher alcohol intake is found in the most deprived groups; it also varies by region (highest in Northern England) and by ethnicity (highest amongst white British people).

• Data is unclear about the prevalence of alcohol withdrawal symptoms and delirium tremens. Most studies suggest that up to 1.8% of people with alcohol use disorder develop delirium tremens upon stopping drinking although others suggest up to 12 % can be affected.⁸

• Up to 50% of people with AUD experience some withdrawal symptoms upon decreasing or stopping.⁹

Acute alcohol withdrawal can be a complex issue. Some patients have no significant symptoms; others have mild alcohol withdrawal symptoms and can be managed in the community depending on their clinical assessment at that time; still others have more severe symptoms or a history of adverse outcomes, and need close inpatient supervision.¹⁰

It is important to recognise that, in the UK, if alcohol withdrawal needs clinical oversight in the community then this should be provided by alcohol and drug services. General practice can offer advice about not reducing alcohol abruptly or too quickly whilst waiting for specialist support and can prescribe prophylactic oral thiamine.²

More specialist drugs to manage the symptoms of withdrawal should not be prescribed in general practice.

Problems associated with alcohol withdrawal can include:

• Uncomfortable withdrawal symptoms, such as anxiety, tremors, headache, nausea/vomiting, diaphoresis, or palpitations .

• Delirium tremens.

• O síndrome de Wernicke-Korsakoff.

• Convulsões.

• Depressão.

• Polysubstance abuse.

• Electrolyte disturbances.

• Complications due to associated liver disease.

Apresentação

This may be in a number of different ways:

• A patient may present in acute alcohol withdrawal.

• A patient may be admitted to hospital for another reason and thus an unplanned alcohol withdrawal may be precipitated. Alcohol-use disorders can complicate the assessment and treatment of other medical and psychiatric problems.

• A patient may present wishing to abstain from alcohol but be seen as at risk of acute alcohol withdrawal.

Alcohol withdrawal symptoms

• Symptoms typically present about eight hours after a significant fall in blood alcohol levels. They peak at about 72 hours and, by day 4 or 5, the symptoms have usually improved significantly.¹¹

• Minor withdrawal symptoms (can appear 6-12 hours after alcohol has stopped):

  • Insomnia and fatigue.

  • Tremor.

  • Mild anxiety/feeling nervous.

  • Mild restlessness/agitation.

  • Náusea e vômito.

  • Dor de cabeça.

  • Suor excessivo.

  • Palpitações.

  • Anorexia.

  • Depressão.

  • Craving for alcohol.

• Alcoholic hallucinosis occurs in about 2% of cases of acute alcohol withdrawal (can appear 12-24 hours after alcohol has stopped):¹¹

  • Includes visual, auditory or tactile hallucinations.

• Withdrawal seizures occur in up to a third of cases of acute alcohol withdrawal (can appear 24-48 hours after alcohol has stopped):

  • These are generalised tonic-clonic seizures.

• Alcohol withdrawal delirium or 'delirium tremens' (can appear 48-72 hours after alcohol has stopped).

• NOTE that alcohol withdrawal shows a "kindling" or sensitisation phenomenon, whereby subsequent withdrawal attempts tend to result in increased severity of symptoms, particularly around seizure activities. Repeated alcohol withdrawals lower the seizure threshold and increase the likelihood of seizures.¹¹

História

Ask about:

• Quantity of alcoholic intake and duration of alcohol use.

• Time since last drink.

• Whether previous alcohol withdrawals have been attempted.

• Medical history including psychiatric history.

• Medication history (including prescribed drugs and drugs of misuse and any drug allergies).

• Support network.

Note that many patients may not actually be trying to stop drinking. They may either have an intercurrent illness stopping them from drinking or problems with alcohol availability.

Treatment of alcohol withdrawal symptoms

The aim of medically assisted withdrawal is to prevent complications including seizures and delirium tremens, as well as making withdrawal more comfortable for the patient and providing an environment where interventions that can help maintain abstinence may be introduced.

Decide on whether the patient needs to be admitted to hospital

• Previous delirium tremens or alcohol withdrawal seizures or presence of autonomic overactivity or age <18 years are all associated with a higher risk of developing acute alcohol withdrawal and these patients should be admitted. Also, consider admission if there are concerns about the patient's safety - eg, living alone or with psychiatric problems. Patients who have failed detoxification at home should also be admitted and it should be considered in those who have other substance misuse.

• Patients with suspected Wernicke's encephalopathy need urgent admission for treatment with intravenous thiamine.

Is medication always needed for detoxification?
Medication may not be needed for detoxification if:

• A male patient is drinking <15 units/day or a female patient is drinking <10 units/day AND they do not report any recent withdrawal symptoms or recent drinking to prevent withdrawal symptoms.

• The patient has no withdrawal signs or symptoms.

A scale has also been suggested to assess the severity of the alcohol withdrawal syndrome: the revised Clinical Institute Withdrawal Assessment for Alcohol scale (CIWA-Ar).¹¹

Medications for acute alcohol withdrawal

Benzodiazepines

• Benzodiazepines are the recommended drugs for detoxification. They have a slower onset of action and therefore are less likely to lead to misuse. A reducing dose of chlordiazepoxide over 5-7 days is commonly used. Diazepam is an alternative.

• Ideally, the patient should be seen daily by their alcohol team and the medication should be dispensed daily.

• The benzodiazepine should be stopped once detoxification is complete or if the patient relapses and starts drinking again during detoxification.

• A British Medical Journal (BMJ) review has suggested the following regimen for moderate alcohol dependence being treated under an alcohol team or as an inpatient (this should not be prescribed by general practice, unless under an agreed and funded shared care arrangement with an alcohol team):

  • Day 1: 20 mg chlordiazepoxide four times daily.

  • Day 2: 15 mg chlordiazepoxide four times daily.

  • Day 3: 10 mg chlordiazepoxide four times daily.

  • Day 4: 5 mg chlordiazepoxide four times daily.

  • Day 5: 5 mg chlordiazepoxide twice daily.

• Dose depends on factors including level of alcohol dependence, sex, weight and current liver function. Smaller doses may be needed for mild dependence and larger doses for severe dependence. People at high risk of seizures or delirium tremens may need a longer period of treatment (maximum of two weeks).

• For mild/moderate alcohol detoxification in secondary care, some hospitals have a system whereby regular reducing doses of chlordiazepoxide are not given due to concerns about sedative effects. They have a point score where nurses regularly make an assessment and, depending on the patient's score, they are given a certain dose of benzodiazepine (usually diazepam).

Thiamine¹²

• Thiamine deficiency is common in people who are alcohol-dependent, due to their poor diet, the presence of gastritis which can affect its absorption, and also the fact that it is a coenzyme in alcohol metabolism.

• Deficiency can cause Wernicke's encephalopathy, which if left untreated, can lead to Korsakoff's syndrome.

• Oral thiamine is poorly absorbed in dependent drinkers. For this reason, all those undergoing detoxification in the community should be considered for admission for parenteral high-potency B complex vitamins (Pabrinex®) as prophylactic treatment. However, because of the risk of anaphylaxis, resuscitation facilities need to be available at the time of administration. The risk of anaphylaxis is lower if the drug is given intramuscularly (IM).

• As prophylactic treatment, 250 mg of thiamine should be given IM or intravenously (IV) once a day for three to five days.

• If the patient is healthy and well nourished and alcohol dependence is uncomplicated then an alternative is oral thiamine at a minimum dose of 300 mg per day during detoxification (given as divided doses).

• Ongoing prescription of lower doses of thiamine is suggested if there is concern about chronic deficiency after this. NICE Clinical Knowledge Summaries (NICE CKS) recommends that 50 mg daily be taken.

Patients may also need to be referred to other specialities - eg, hepatologists, psychiatrists.

This is a medical emergency. A hyperadrenergic state is present. The prevalence of DT in the general population is <1% and nearly 2% in patients with alcohol dependence.¹⁴

Características clínicas

• Delirium tremens usually begins 24-72 hours after alcohol consumption has been reduced or stopped .

• The symptoms/signs differ from usual withdrawal symptoms in that there are signs of altered mental status. These can include:

  • Hallucinations (auditory, visual, or olfactory).

  • Confusão.

  • Delusions.

  • Severe agitation.

• Seizures can also occur.

• Examination may reveal signs of chronic alcohol abuse/stigmata of chronic liver disease. There may also be:

  • Taquicardia.

  • Hyperthermia and excessive sweating.

  • Hipertensão.

  • Taquipneia.

  • Tremor.

  • Mydriasis.

  • Ataxia.

  • Altered mental status.

  • Cardiovascular collapse.

Fatores de risco

• Previous history of delirium tremens.

• Previous history of alcohol withdrawal seizures.

• Co-existing infection or medical problems including pancreatitis or hepatitis.

• Recent higher-than-normal levels of alcohol intake.

• Idade avançada.

• Abnormal liver function.

• More severe withdrawal symptoms on presentation.

Investigações

This is a clinical diagnosis and there is often a known history of alcohol misuse/dependence.

• Blood tests can help to assess other medical problems. Dehydration and electrolyte disturbance may be present. Tests can include:

  • Hemograma completo.

  • Testes de função hepática.

  • Clotting.

  • Arterial blood gases (to look for metabolic acidosis).

  • Glicose.

  • Blood alcohol levels.

  • U&Es e creatinina.

  • Amylase.

  • Creatine phosphokinase (especially if the patient was unconscious for a long time, due to risk of rhabdomyolysis).

  • Blood cultures (if there are concerns about infection).

• CXR should be considered if there are signs of respiratory distress. Co-existing pneumonia is common. There is also the possibility of aspiration, especially if reduced consciousness or seizures have occurred.

• CT scan of the head may be needed if there are seizures or there is evidence of a recent head injury.

• ECG may show an arrhythmia.

Gestão

• This should be in a hospital setting. Intensive care may be needed for very unwell patients.

• It should first include assessment and management of 'Airway, Breathing and Circulation (ABC)' .

• Any hypoglycaemia should be treated.

• Sedation with benzodiazepines is suggested. Diazepam or lorazepam are preferred depending on treatment regime.

• In benzodiazepine refractory cases, phenobarbital, propofol, and dexmedetomidine could be used.^{14 15}

• Patients with delirium tremens may also have Wernicke's encephalopathy and should be treated for both conditions:

  • At least two pairs of ampoules of Pabrinex® (500 mg thiamine) should be given IV three times daily for three days.

  • If the patient does not respond, treatment should be discontinued.

  • If signs or symptoms respond to treatment, continue with two ampoules of Pabrinex® once daily for five days or for as long as improvement continues.

Prognóstico

The mortality rate with early recognition and treatment is less than 5%.¹⁶

• Close follow-up is needed.

• Counselling, self-help and groups including Alcoholics Anonymous may be helpful.

• Drugs can be used in abstinence to help prevention of relapse. These are discussed in the separate Alcoholism and alcohol dependence - management article. Again these should be prescribed by alcohol services who have the skills and expertise to manage them.

• Any co-existing medical and psychological problems should also be addressed.

• If problem drinking is identified early, it may mean that complications, including severe alcohol withdrawal and delirium tremens, are avoided.

• Patients admitted to hospital should always be screened for alcohol dependence.

• There is some evidence that a ketogenic diet reduces withdrawal symptoms.¹⁷