Alcohol Intoxication

Alcohol Intoxication occurs when there is a clinically significant problematic behavioural or psychological change (e.g. - inappropriate sexual or aggressive behavior, impaired social or occupational functioning, mood lability, impaired judgment) that develops during, or shortly after ingestion.[1]

Epidemiology
  • The majority of alcohol users are likely to have experienced intoxication to some degree at some point in their lives.[2]
    • In the United States, the average age of first intoxication is around 15 years, and the highest prevalence at between ages 18 to 25 years.[3]
  • A 2010 United States survey found that 44% of grade 12 students endorsed being “drunk in the past year,” and >70% of college students reported the same.[4]
Prognosis
  • An episode of intoxication usually develops over minutes to hours and usually lasts several hours.
  • Alcohol intoxication is a high risk contributor to suicidal behaviour and attempts.[5]
  • The frequency and intensity of alcohol intoxication usually decreases with older age.
Comorbidity
  • The earlier the age of onset of regular intoxication, the greater risk for later developing alcohol use disorder.
  • Alcohol intoxication may occur with other substance intoxications, especially in individuals with antisocial personality disorder or conduct disorder.
  • In the United States, alcohol intoxication contributes to the more than 30,000 related deaths each year.[6]
    • Alcohol use and intoxication is estimated to account for up to 55% of fatal driving events.[7]
Risk Factors
  • Environmental factors such as peer pressure, and personality characteristics such as sensation/novelty seeking and impulsivity are risk factors.[8]
Cultural
  • Cultural factors play a large role in alcohol intoxication. Certain dates of cultural significance may encourage alcohol intoxication (e.g. - New Year's Eve), while other religious affiliations may prohibit any drinking or intoxication. Certain environments, such as bars and colleges also encourage intoxication.[9]
Criterion A

Recent ingestion of alcohol.

Criterion B

Clinically significant problematic behavioural or psychological changes (e.g. - inappropriate sexual or aggressive behaviour, mood lability, impaired judgment) that developed during, or shortly after, alcohol ingestion.

Criterion C

At least 1 of the following signs or symptoms developing during, or shortly after, alcohol use:

  1. Slurred speech
  2. Incoordination
  3. Unsteady gait
  4. Nystagmus
  5. Impairment in attention or memory
  6. Stupor or coma
Criterion D

The signs or symptoms are not attributable to another medical condition and are not better explained by another mental disorder, including intoxication with another substance.

  • Alcohol intoxication is sometimes associated with amnesia during the course of the intoxication (“blackouts”).
  • Throughout Canada and the United States, the maximum legal blood alcohol concentration (BAC) for drivers is 80 mg of alcohol in 100 mL of blood, or a BAC of 0.08.
    • Driving with a BAC over 0.08 is a criminal offence in most jurisdictions.
  • The BAC can also be used to judge tolerance to alcohol.
    • For example, an individual with a concentration of 150 mg/dL who does not show signs of intoxication can be presumed to have at least some degree of tolerance. At 200 mg/dL, most non-tolerant individuals will have severe intoxication.

Blood alcohol level and associated symptoms

BAC (%) Serum blood (mg/dL) Serum blood (mmol/L) Symptoms
0.01-0.04 10-40 2-9 No loss of coordination, slight euphoria, loss of shyness
0.04-0.06 40-60 9-13 Well-being feeling, relaxation, lower inhibitions, minor impairment of reasoning and memory, euphoria
0.07-0.09 70-90 15-20 Slight impairment of balance, speech, vision, reaction time, and hearing, euphoria. Judgment and self-control reduced. Caution, reasoning, and memory are impaired.
0.10-0.13 100-125 22-27 Significant impairment of motor coordination and loss of good judgment. Speech may be slurred; balance, vision, reaction time and hearing will be impaired. Euphoria.
0.13-0.15 130-150 28-32 Gross motor impairment and lack of physical control. Blurred vision and major loss of balance. Euphoria is reduced and dysphoria is beginning to appear.
0.16-0.20 160-200 35-43 Dysphoria (anxiety, restlessness) predominates, nausea may appear. Individual appears heavily inebriated and may be unable to take care of hygiene.
0.25 250 54 Needs assistance in walking; total mental confusion. Non-tolerant individuals are likely asleep. Dysphoria with nausea and some vomiting can occur.
0.30 300 65 Loss of consciousness
>0.40 400 87 Onset of coma, possible death due to respiratory depression/arrest. Death is possible in non-tolerant individuals.

How Do I Convert between BAC, mmol/L, and g/dL?

  • 1 mmol of ethanol per 1 L of blood = 4.61 mg of ethanol per 100 mL (i.e. - 100mg/dL, per decilitre, or one tenth of a litre) of blood.
  • 100 mg/dL = 0.10 (g/dL) BAC, or 0.10%. (i.e. — divide by 1000 to get the BAC)
  • To convert from BAC to mmol/L, ([BAC]*1000)/4.61 = mmol/L

Factors That Affect Alcohol Levels

Numerous factors can affect the blood alcohol concentration, including:
  • Age (BAC increases with age)
  • Gender (BAC is usually higher in women due to lower water content in their bodies)
    • Additionally, women have lower levels of gastric alcohol dehydrogenase.[10]
  • The rate of consumption
  • Drink strength
  • Body size (smaller weight equals higher BAC)
  • Fat/muscle content (BAC is higher in those with higher percent body fat, and lower in those with more muscle mass)
  • Metabolism
  • Medication interactions
  • Food (drinking on an empty stomach will lead to higher BAC)

Alcohol and Diabetes

In patients with diabetes, alcohol ingestion can cause hypoglycaemia, particularly in Type I Diabetes, and Type II diabetics who use insulin.
  • Alcohol elimination follows zero-order kinetics:[11]
    • In non-tolerant adults, the elimination is an average of 3.26 to 4.35 mmol/L per hour (15 to 20 mg/dL)
    • In tolerant adults, it is an average of 6.5 to 8.7 mmol/L per hour
  • Other medical conditions
    • Several medical (e.g. - diabetic acidosis, hyponatremia) and neurological conditions (e.g. - stroke, cerebellar ataxia, multiple sclerosis) can temporarily resemble alcohol intoxication.
    • Intoxication with sedative, hypnotic, or anxiolytic drugs or with other sedating substances (e.g. - antihistamines, anticholinergic drugs) can be mistaken for alcohol intoxication. The differential requires observing alcohol on the breath, measuring blood or breath alcohol levels, ordering a medical workup, and gathering a detailed history.
    • The signs and symptoms of sedative-hypnotic intoxication are very similar to those observed with alcohol and include similar problematic behavioural or psychological changes. Unlike with alcohol, there is no smell of intoxication, but there is likely to be evidence of misuse of the depressant drug in the blood or urine toxicology analyses.
  • Evidence for alcohol intoxication may be evident by smelling alcohol on the individual's breath, gathering a history from the individual or another observer, or having the individual provide a breath, blood, or urine sample for toxicology analysis.[12]
  • In the absence of severe cardiorespiratory compromise (in which case acute and critical care may be needed), alcohol intoxication is usually managed conservatively.
  • Intravenous fluids should be given for dehydration.
  • In the cases of acute agitation during intoxication, agitation can be managed using acute emergency medications such as antipsychotics.
    • However, respiration should be carefully monitored as this increases the risk for respiratory compromise. Benzodiazepines should not be prescribed due to the risk for further respiratory depression.

Alcohol Use Disorder Guidelines

Guideline Location Year PDF Website
Canadian Guidelines on Alcohol Use Disorder Among Older Adults Canada 2020 - Link
British Columbia Centre on Substance Use (BCCSU) Canada 2019 Link Link
National Institute for Health and Care Excellence (NICE) UK 2011 - Link
American Psychiatric Association (APA) USA 2018 - Link
For Patients
For Providers
Articles
Research
1) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
2) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
3) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
4) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
5) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
6) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
7) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
8) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
9) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
12) American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.