Alcohol (drug)

Alcohol, sometimes referred to by the chemical name ethanol, is a psychoactive drug that is the active ingredient in drinks such as beer, wine, and distilled spirits (hard liquor).[11] It is one of the oldest and most common recreational substances, causing the characteristic effects of alcohol intoxication ("drunkenness").[12] Among other effects, alcohol produces happiness and euphoria, decreased anxiety, increased sociability, sedation, impairment of cognitive, memory, motor, and sensory function, and generalized depression of central nervous system function. Ethanol is only one of several types of alcohol, but it is the only type of alcohol that is found in alcoholic beverages or commonly used for recreational purposes; other alcohols such as methanol and isopropyl alcohol are significantly more toxic.[11] A mild, brief exposure to isopropanol, being only moderately more toxic than ethanol, is unlikely to cause any serious harm. Methanol, being profoundly more toxic than ethanol, is lethal in quantities as small as 10–15 milliliters (2–3 tsp).

Ethanol
Clinical data
Pronunciation/ˈɛθənɒl/
Other namesAbsolute alcohol; Alcohol (USP); Cologne spirit; Drinking alcohol; Ethanol (JAN); Ethylic alcohol; EtOH; Ethyl alcohol; Ethyl hydrate; Ethyl hydroxide; Ethylol; Grain alcohol; Hydroxyethane; Methylcarbinol
Dependence
liability
Moderate[1]
Addiction
liability
Moderate (10–15%)[2]
Routes of
administration
Common: by mouth
Uncommon: suppository, inhalation, ocular, insufflation, injection[3]
Drug classAnalgesic; Depressants; Sedatives; Anxiolytics; Euphoriants; GABAA receptor positive modulators
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability80%+[4][5]
Protein bindingWeakly or not at all[4][5]
MetabolismLiver (90%):[6][7]
Alcohol dehydrogenase
MEOS (CYP2E1)
MetabolitesAcetaldehyde; Acetate; Acetyl-CoA; Carbon dioxide; Water; Ethyl glucuronide; Ethyl sulfate
Onset of actionPeak concentrations:[6][4]
• Range: 30–90 minutes
• Mean: 45–60 minutes
Fasting: 30 minutes
Elimination half-lifeConstant-rate elimination at typical concentrations:[8][7][6]
• Range: 10–34 mg/dL/hour
• Mean (men): 15 mg/dL/hour
• Mean (women): 18 mg/dL/hr
At very high concentrations (t1/2): 4.0–4.5 hours[5][4]
Duration of action6–16 hours (amount of time that levels are detectable)[9]
Excretion• Major: metabolism (into carbon dioxide and water)[4]
• Minor: urine, breath, sweat (5–10%)[6][4]
Identifiers
  • ethanol
CAS Number
  • 64-17-5
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
PDB ligand
Chemical and physical data
FormulaC2H6O
Molar mass46.069 g·mol−1
3D model (JSmol)
Density0.7893 g/cm3 (at 20 °C)[10]
Melting point−114.14 ± 0.03 °C (−173.45 ± 0.05 °F) [10]
Boiling point78.24 ± 0.09 °C (172.83 ± 0.16 °F) [10]
Solubility in waterMiscible mg/mL (20 °C)
  • CCO
  • InChI=1S/C2H6O/c1-2-3/h3H,2H2,1H3
  • Key:LFQSCWFLJHTTHZ-UHFFFAOYSA-N

Alcohol has a variety of short-term and long-term adverse effects. Short-term adverse effects include generalized impairment of neurocognitive function, dizziness, nausea, vomiting, and hangover-like symptoms. Alcohol is addictive to humans, and can result in alcohol use disorder, dependence and withdrawal. It can have a variety of long-term adverse effects on health, for instance liver damage,[13] brain damage,[14][15] and its consumption is the fifth leading cause of cancer.[16][failed verification] The adverse effects of alcohol on health are most important when it is used in excessive quantities or with heavy frequency. However, some of them, such as increased risk of certain cancers, may occur even with light or moderate alcohol consumption.[17][18] In high amounts, alcohol may cause loss of consciousness or, in severe cases, death.

Alcohol works in the brain primarily by increasing the effects of a neurotransmitter called γ-aminobutyric acid, or GABA.[19] This is the major inhibitory neurotransmitter in the brain, and by facilitating its actions, alcohol suppresses the activity of the central nervous system.[19] The substance also directly affects a number of other neurotransmitter systems including those of glutamate, glycine, acetylcholine, and serotonin.[20][21] The pleasurable effects of alcohol ingestion are the result of increased levels of dopamine and endogenous opioids in the reward pathways of the brain.[22][23] Alcohol also has toxic and unpleasant actions in the body, many of which are mediated by its byproduct acetaldehyde.[24]

Alcohol has been produced and consumed by humans for its psychoactive effects for almost 10,000 years.[25] Drinking alcohol is generally socially acceptable and is legal in most countries, unlike with many other recreational substances. However, there are often restrictions on alcohol sale and use, for instance a minimum age for drinking and laws against public drinking and drinking and driving.[26] Alcohol has considerable societal and cultural significance and has important social roles in much of the world. Drinking establishments, such as bars and nightclubs, revolve primarily around the sale and consumption of alcoholic beverages, and parties, festivals, and social gatherings commonly involve alcohol consumption. Its use is also related to various societal problems, including driving accidents and fatalities, accidental injuries, sexual assaults, domestic abuse, and violent crime.[27] Alcohol remains illegal for sale and consumption in a number of countries, mainly in the Middle East. While some religions, including Islam, prohibit alcohol consumption, other religions, such as Christianity and Shinto, utilize alcohol in sacrament and libation.[28][29][30]