Many people do not think of alcohol as a drug. However, alcohol is a drug that affects the body in various ways, depending on the dose. Blood alcohol concentration (BAC) is the amount of alcohol present in a person’s bloodstream. It is determined by the speed of consumption as well as the drinker’s weight, sex, build and metabolism.

As the BAC increases, the brain and spinal cord (central nervous system) show progressively less activity. A BAC of 50 mg/dL (milligrams per deciliter) of blood, for example, usually leads to a state of mild intoxication. A BAC of 100 to 150 leads to slurring, loss of balance and other signs of intoxication in most people. Coma is likely at a BAC of 350, and death will probably occur at 500.

Through a process called oxidation, alcohol is detoxified and removed from the blood. The higher the BAC, the longer this process takes and the longer normal bodily function and activity are affected. Alcohol is metabolized (broken down) from the body more slowly than it is absorbed. The more an individual drinks, the harder the metabolism works to break it down so the body can absorb it before intoxication and even poisoning can occur.

The effects of alcohol are also influenced by an individual’s mental and emotional state, individual tolerance for alcohol and the presence of other medications in the body at the time of consumption. The amount and type of food in the stomach before drinking alcohol is also a factor in the rate of absorption into and elimination from the body.

When deciding whether or not to drink, people should consider the potential effects alcohol may have on their health. For people with diabetes, this decision is especially important.

Occasionally drinking alcohol is normally acceptable as long as the patient’s diabetes is under control and the patient is aware of alcohol’s potential effects. It is extremely important for patients to discuss alcohol with their physician. Certain medications do not mix well with alcohol, and alcohol can worsen some medical conditions. Patients should consume alcohol only if their physician has agreed that it is safe.

As with the general population, diabetic women should avoid alcohol during pregnancy or when trying to become pregnant. Diabetes patients should also avoid alcohol if they suffer frequent episodes of hypoglycemia or hypoglycemia unawareness. Patients with certain medical conditions including pancreatitis, liver disease and, of course, alcoholism also should not consume alcohol.

A diabetic complication that may rule out use of alcohol is a gastroparesis, a form of autonomic neuropathy that affects the stomach. Furthermore, alcohol can worsen or increase the risk of developing diabetic neuropathy and other complications, including diabetic retinopathy, lipid problems and erectile dysfunction, according to the American Diabetes Association.

It is primarily the liver’s job to break down alcohol in the body. It takes the liver about one hour to metabolize 1/2 ounce (15 milliliters [ml]) of alcohol. For an average man, the body would require about two hours to metabolize 1 ounce (30 ml) of alcohol, the typical amount in one drink. When a person consumes alcohol at a faster rate than the liver can break it down, the alcohol moves through the blood to other areas of the body.

As a general guideline, men should consume no more than two drinks a day and women no more than one drink a day. Women are allotted less alcohol because they metabolize it at a slower rate. One drink is defined as:

• One 12-ounce (355-ml) bottle of beer or wine cooler
  
  
• One 5-ounce (148-ml) glass of wine
  
  
• 1.5 ounces (44-ml) of 80-proof distilled spirits

Patients are advised not to exceed this recommendation – or an amount specified by their physician - because doing so can quickly lead to hypoglycemia. Because alcohol cannot be used by the body as a source of glucose (blood sugar), it should be consumed with a meal or large snack.

The risk of alcohol causing low glucose is greatest for people taking insulin or antidiabetic agents because these medications are already working to reduce glucose levels. The risk of hypoglycemia is significantly less in people with type 2 diabetes who control the disease with exercise and meal planning alone.