05 - Alcohol withdrawal

Alcohol withdrawal

480 The Maudsley® Prescribing Guidelines in Psychiatry CHAPTER 4 The following structured assessment tools are recommended:2 ■ ■The Alcohol Use Disorders Identification Test (AUDIT)4 questionnaire is a ­10-­item questionnaire which is useful as a screening tool in those identified as being at increasing risk. Questions 1–3 address the quantity of alcohol consumed, 4–6 the signs and symptoms of dependence and 7–10 the behaviours and symptoms associated with harmful alcohol use. Each question is scored 0–4, giving a ­maximum total score of 40. A score of 8 or more is suggestive of hazardous or harmful alcohol use. Hazardous drinking = consumption of alcohol likely to cause harm. Harmful drinking = ­consumption already causing mental or physical health problems. ■ ■The Severity of Alcohol Dependence Questionnaire (SADQ)5 is a more detailed 20-­item questionnaire with the score on each item ranging from 0 to 3, giving a ­maximum total score of 60. Severity of alcohol dependence Mild

SADQ score of 15 or less Moderate

SADQ score 15–30 Severe

SADQ score >30 Alcohol withdrawal In alcohol-­dependent drinkers, the central nervous system (CNS) has adjusted to the constant presence of alcohol in the body (neuroadaptation). When the blood alcohol concentration (BAC) is suddenly lowered, the brain remains in a hyper-­excited state, resulting in the withdrawal syndrome (Tables 4.1 and 4.2). There is no evidence to support prophylactic use of additional anticonvulsant medication to prevent seizures in high-­risk individuals. Table 4.1  Mild alcohol withdrawal. Mild alcohol withdrawal manifestations Usual timing of onset after last drink Other information Agitation/anxiety/irritability Tremor of hands, tongue, eyelids Sweating Nausea/vomiting/diarrhoea Fever Tachycardia Systolic hypertension General malaise Onset at 3–12 hours Peak at 24–48 hours Duration up to 14 days Symptoms are non-­specific Absence does not exclude withdrawal May commence before blood alcohol levels reach zero Management ■ ■May be self-­limiting but mitigated with adequate benzodiazepine cover and supportive treatment. ■ ■Monitor vital signs. Use a withdrawal assessment scale. ■ ■See Table 4.2 for the various benzodiazepine regimens recommended.

Addictions and substance misuse CHAPTER 4 Table 4.2  Severe alcohol withdrawal. Severe alcohol withdrawal complications Usual timing of onset after last drink Other information Generalised seizures 12–18 hours May commence before blood alcohol levels reach zero Management ■ ■The occurrence of a first seizure during medically assisted withdrawal requires investigation to rule out organic disease or idiopathic epilepsy. ■ ■A meta-­analysis of trials assessing the efficacy of drugs preventing alcohol withdrawal seizures demonstrated that benzodiazepines, particularly long-­acting preparations such as diazepam, significantly reduced seizures de novo.6,7 ■ ■Long-­acting benzodiazepine is recommended as prophylaxis in those with a previous history of seizures.8 ■ ■Some anticonvulsants are as effective as benzodiazepines, with some units recommending carbamazepine loading in patients with untreated epilepsy, or where seizures have occurred despite adequate benzodiazepine loading.6 ■ ■Phenytoin does not prevent alcohol withdrawal-­related seizures when used on its own or in combination with benzodiazepines.9 There is no need to continue anticonvulsants long term when used to prevent seizures in alcohol withdrawal.9 Delirium tremens Clouding of consciousness/confusion Vivid hallucinations, particularly in visual and tactile modalities Marked tremor Other clinical features also include: autonomic hyperactivity (tachycardia, hypertension, sweating and fever), paranoid delusions, agitation and insomnia Prodromal symptoms include: night-­time insomnia, restlessness, fear and confusion Risk factors: severe alcohol dependence, self-­detoxification without medical input, multiple previous admissions for alcohol withdrawal, concurrent medical illness, previous history of delirium tremens and alcohol withdrawal seizures, low potassium, low magnesium, thiamine deficiency, inadequately treated withdrawal Recognition is important because treatment is different from delirium arising from other causes; delirium tremens needs larger doses of benzodiazepines and more caution with antipsychotics 3–4 days (72–96 hours) Develops in 3–5% of those admitted to hospital for alcohol withdrawal A medical emergency Mortality 10–20% if untreated Management ■ ■Delirium tremens is a medical emergency and requires prompt transfer to a general hospital,9 preferably to a high-­dependency setting.10,11