The "active" ingredient in drinking alcohol is ethanol or ethyl alcohol. Ethanol, despite it's legality, is considered to be a sedative-hypnotic drug (also know as a "downer") that affects the brain like other sedative-hypnotic drugs, like Valium and other barbiturates would do.

Prolonged consumption of ethanol is known to cause physical dependence in many individuals. Physical dependence can include the following symptoms:

* Confusion, hypervigilance and disorientation (which happens under excessive consumption as well)
* High body temperature, increased blood pressure and pulse and respiration
* Increased restlessness, anxiety and insomnia
* Hallucinations and psychotic behavior

While physical dependence is dangerous, it is not considered to be an "addiction". There are similarities between physical dependence and addiction, but there are significant differences. "Alcohol Addiction" is a complex behavioral syndrome where:

* An individual's use of alcohol is done to extremes
* Alcohol use is rationalized or minimized
* Alcohol use results in personality changes and
* Alcohol use results in negative consequences, whether financial, personal, health or other.

For more information about Alcoholism and Addiction, check out

Blood Alcohol Information and Alcohol and Drug Abuse.

The best way to estimate your blood alcohol concentration, without the use of a breathalyzer, is by the use of charts that have been developed to serve as a general guide to blood alcohol concentration. Keep in mind, these charts are made for the general population - everybody reacts differently to alcohol, so factors like general health and the body's metabolism will have a significant affect, and can therefore cause quite a variance.

Those prone to higher blood alcohol concentrations are:

* Individuals in poor health, especially those with poor livers
* Females [Content Related to Females] , especially those with low body weight [Content Related to body weight]
* Males with low body weight

The reason why females and low-body-weight males are prone to higher blood alcohol concentration is because they will generally have less blood volume to dilute the alcohol, as well as a lesser capacity to break the alcohol down in the same amount of time as a male or heavier female.

NB: The charts you will be using are only guides. Do not use information from this chart to decide whether to drive after drinking! The safest blood alcohol concentration for driving is zero!

Using the blood alcohol concentration chart to calculate your estimated blood alcohol content requires four pieces of information - your gender, your weight, how many drinks you have had and how much time has elapsed since your first drink. The charts differ for males and females, so click the appropriate link below.

Female Blood Alcohol Concentration Chart
Male Blood Alcohol Concentration Chart

Alcohol can affect several parts of the brain, but in general, alcohol contracts brain tissue and depresses the central nervous system. Also, alcohol destroys brain cells and unlike many other types of cells in the body, brain cells do not regenerate. Excessive drinking over a prolonged period of time can cause serious problems with cognition and memory.

When alcohol reaches the brain, it interferes with communication between nerve cells, by interacting with the receptors on some cells. The alcohol suppresses excitatory nerve pathway activity and increases inhibitory nerve pathway activity. Among other actions, alcohol enhances the effects of the inhibitory neurotransmitter GABA. Enhancing an inhibitor has the effect of making a person sluggish. Also, alcohol weakens the excitatory neurotransmitter glutamine, which enhances the sluggishness even farther.

To understand how alcohol interferes with brain function, it is necessary to know a little bit about normal brain function. The brain is the control center of the body - it controls all the systems in your body including your muscular system, your respiratory system and your digestive system. But how does the brain control these functions? It does so by using a series of chemical, electrical and physical signals from cell to cell. Within the cell, electrical signals are used for transmission, but between cells, chemical signals are used - these chemical signals are called neurotransmitters.

The gap between cells where neurotransmitters are active is called the synapse. The expelled neurotransmitter travels across the synapse and binds to a protein on the receiving cell membrane called a receptor, which is specific for that neurotransmitter. This action causes some change in the receiving cell, either chemical, electrical or physical, which can excite the receiving cell to perform an action or inhibit the receiving cell from performing an action.

When alcohol is introduced to the synapse, the normal neurotransmission may be affected.

For information on how alcohol effects different parts of the brain, see the specific pages here:

The Cerebral Cortex and Alcohol
The Limbic System and Alcohol
The Cerebellum and Alcohol
The Hypothalamus, Pituitary Gland and Alcohol
The Medulla and Alcohol

Before describing the affects of alcohol on the body, you should know how alcohol enters the body and what it does when it gets there. After alcohol is ingested, it reaches the stomach where about 20% of the alcohol absorbs into the blood stream, through small blood vessels. The remaining 80% of the alcohol continues to the small intestine and is absorbed there into the blood stream.

The alcohol flows through the blood stream and is metabolized by the liver, where the alcohol is broken down by enzymes. The liver can, on average, metabolize about one standard drink (i.e. one 12 ounce bottle of beer, one 4 ounce glass of wine or 1.5 ounces of 40% alcohol) in one hour. Alcohol consumed in addition to these amounts can generally not be processed by the liver. When this happens, your blood becomes saturated and the additional alcohol makes its way to your body tissues and blood stream, until your liver can process the excess alcohol.

When consumed in large amounts over a prolonged period of time, alcohol can harm virtually every part of your body. Many of the effects are reversible if alcohol consumption is subsequently controlled - other effects are permanent.

Often people would think twice about their abuse of alcohol if they understood how alcohol is affecting their body in large quantities. To understand the affects of alcohol on each body part, please use the links below:

Alcohol and Blood
Alcohol and the Esophagus
Alcohol and the Heart
Alcohol and the Joints and Muscles
Alcohol and the Kidneys
Alcohol and the Liver
Alcohol and the Lungs
Alcohol and the Pancreas
Alcohol and the Reproductive System
Alcohol and the Small Intestines
Alcohol and the Stomach