Alcohol and Other Drug Facts

How is Blood Alcohol Content (BAC) measured?

Blood Alcohol Content (BAC) is a measure of alcohol in the blood as a percentage. It is calculated in grams per 100 mL of blood, so a BAC of 0.08 means your blood is 0.08% alcohol by volume.

Standard Servings - What Counts as One Drink?

A standard serving of alcohol, or "one drink" contains 14 grams (0.5 oz) of pure alcohol.

The amount of alcohol in a drink is more important than the volume of liquid. Different types of drinks contain different concentrations of alcohol. You might see the concentration of alcohol in the drink expressed as a percent (e.g. 40% alcohol y volume, or AbV), or as a proof. Proof is simply the percentage multiplied x2, so a drink with 40% alcohol by volume is 80 proof. Below are examples of alcoholic drinks, their alcohol by volume (or percentage of alcohol) and standard serving sizes. 


Signs of Alcohol Poisoning 

Alcohol poisoning is a life-threatening condition caused by high concentrations of alcohol in the blood. Blood alcohol concentration (BAC) rises as alcohol is consumed in large quantities and over short periods of time. 


  • Person cannot be awakened
  • Person has cold, clammy, pale, or bluish skin
  • Person has slow, shallow, or irregular breathing
  • Person is vomiting while passed out and does not wake up

The depressant effects of alcohol can slow the breathing and heart rate down to a point where a person enters a coma and may die.

If You Suspect Alcohol Poisoning

  • Call Public Safety (937-229-2121) if someone is showing symptoms of alcohol poisoning
  • Do not leave them alone or put them in bed to "sleep it off", continue to monitor them until help arrives
  • If they pass out, put them on their side to prevent choking on vomit

Prevent Alcohol Poisoning 

Prevent alcohol poisoning by only using alcohol in moderation. Following these risk reduction techniques will lower the chances of developing alcohol poisoning. 

photo with risk reduction tips


Tolerance means that after continued drinking, consumption of a constant amount of alcohol produces a lesser effect or increasing amounts of alcohol are necessary to produce the same effect. Your BAC is still rising, but you no longer feel it's effects. 

With tolerance, you feel less drunk, so you’re less able to accurately judge your ability to function. Your body no longer protects you the way it is meant to – since you’re less likely to vomit or pass out, you may reach even higher, more toxic BAC levels. When you develop tolerance, you can no longer experience the “buzz” – you don’t get the same euphoric effects at low doses.

Humans develop tolerance when their brain functions adapt to compensate for the disruption caused by alcohol. "Chronic heavy drinkers display functional tolerance when they show few obvious signs of intoxication even at high blood alcohol concentrations (BAC's), which in others would be incapacitating or even fatal"(Chesher & Greeley, 1992).

Just because you have developed a tolerance doesn't mean you're immune from alcohol's impact on the body. Even with tolerance, the body faces impairment. 
  • Impaired eye-hand coordination
  • Impaired balance
  • Impaired motor function
  • Decreased peripheral vision
  • Tolerance and withdrawal are the two things that distinguish alcohol abuse from alcohol dependence – if you’re building your tolerance, you’re moving toward physical addiction.

Factors that influence intoxication

There are many factors that influence levels of intoxication. Described below are a variety of factors that may magnify intoxication and should be avoided. Drinking responsibly involves being educated about how much alcohol is in your drink, your blood alcohol concentration (BAC), and the environment in which you choose to drink.

  • Quantity of Alcohol & Speed of Consumption - Drinking large quantities of alcohol, especially in short amounts of time. This rises your body's Blood Alcohol Content (BAC) to potentially dangerous levels. 
  • Biological/Genetic Risk - Gemetic factors influence alcoholism. Children of alcoholics are about four times more likely than the general population to develop alcohol problems. People with a family history of alcoholism, who have a higher risk for becoming dependent on alcohol, should approach moderate drinking carefully. 
  • Body Size and Composition - Smaller stature individuals will become impaired quicker. Alcohol can be distributed throughout the body via the circulatory system, and enters most tissues except bone and fat (adipose tissue). Body composition is important, because as the percentage of body fat increases, the resulting concentration of alcohol in the lean tissues of the body is proportionally higher.
  • Stomach Content - Food in the stomach will slow the absorption of alcohol into the bloodstream and delay impairment. Larger meals in closer proximity to time of drinking can lower the peak blood alcohol concentration. 
  • Dehydration - Alcohol in the bloodstream causes the pituitary gland in the brain to block the creation of vasopressin. This causes the kidneys to send water directly to the bladder rather than reabsorbing filtered water into the bloodstream. This diuretic effect increases as the blood alcohol content increases, and can lead to dehydration. 
  • Carbonated Beverages - Carbonation speeds up alcohol absorption into the body. Alcohol mixed with carbonated beverages such as pop or tonic water will be absorbed more quickly into the bloodstream. This is also true for champagne and wine coolers.
  • Energy Drinks - Energy drinks are stimulants and alcohol is a depressant. Energy drinks mask the effects of alcohol by giving you a sense of energy, and the false sense that you are not that intoxicated. Mixing alcohol and energy drinks can cause heart failure because they are opposing stressors on the body’s regulatory systems.
  • Moods - Strong emotions such as anger, fear, and loneliness tend to hasten impairment. The psychological and social effects of alcohol (and the placebo effects) are also magnified by expectations.
  • Marijuana - Marijuana reduces nausea, which can inhibit the body’s ability to remove harmful toxins by vomiting. Marijuana can increase the threshold required to illicit a vomit response.
  • Over-the-Counter Drugs - Do not mix alcohol with aspirin, ibuprofen (Advil), or acetaminophen (Tylenol). These drugs are also metabolized by the liver. What you take isn’t the active form, but is transformed in the liver into the active agent. Drinking alcohol while taking painkillers creates a “bottleneck” in the liver. The drug is processed incorrectly, the bi-products kill liver cells, and alcohol is metabolized slower.  It’s also important not to mix alcohol with other depressants, which includes some antihistamines.
  • Prescription Drugs - Mixing alcohol with prescription drugs often leads to increased or hastened impairment. Alcohol can produce hazardous side effects, reduce heart rate, and drop blood pressure to a dangerous level.

Center for Alcohol and Other Drugs Resources and Education

Adele Center
300 College Park
Dayton, Ohio 45469 - 2610