What Are the Short-Term Effects of Alcohol?

Medically reviewed by Michael Menna, DO

Alcohol (ethanol) is an intoxicating substance found in beverages like wine, beer, and liquor. Shortly after consumption, your body rapidly absorbs alcohol into the bloodstream. Once in the bloodstream, alcohol affects every organ in the body, including your brain.

Drinking any amount or type of alcohol has a wide range of short- and long-term effects on your physical and mental health. As a central nervous system depressant, alcohol slows the body's systems and leads to noticeable changes in cognitive and physical functions.

This article discusses everything you need to know about the short-term effects of alcohol.

How Long Does It Take for Short-Term Effects of Alcohol to Appear?

The short-term effects of alcohol appear quickly, typically within minutes after consuming your first drink. As you drink an alcoholic beverage, alcohol moves into your bloodstream through the stomach and small intestine.

Within five minutes, alcohol reaches your brain, slowing down the central nervous system and affecting the way you feel, think, and behave.

While the short-term effects of alcohol are universal, the time they take and the intensity of these effects vary from person to person. Alcohol can also affect the same person differently, depending on certain factors, including: 

• Amount consumed: The more alcohol you drink, the higher your blood alcohol concentration (BAC) rises.

• Alcohol content: Whiskey and other spirits with 40% alcohol per serving (1.5 ounces) tend to have more rapid effects compared to lower-alcohol alternatives like beer, which has 5% alcohol per serving (12 ounces).

• Drinking pace: Quickly consuming alcohol leads to a more rapid rise in BAC and quicker onset of short-term effects vs. drinking at a slower pace.

• Body weight: People with lower body weight tend to feel the effects of alcohol more quickly and intensely than heavier people. Essentially, the more you weigh, the more water your body contains. Higher water volumes in the body dilute alcohol.

• Sex: Females tend to have more body fat and less water per pound of body weight than males, which can lead to a higher BAC in females.

• Food in your stomach: Having food in your stomach slows down the rate of alcohol absorption and reduces the intensity of alcohol's short-term effects.

• Medication or drugs: Drinking alcohol while taking certain medications or using drugs can increase the effects of each substance and increase the risk of harmful interactions.

A Note on Gender and Sex Terminology

Verywell Health acknowledges that sex and gender are related concepts, but they are not the same. To accurately reflect our sources, this article uses terms like “female,” “male,” “woman,” and “man” as the sources use them.

Feelings of Relaxation or Drowsiness

As alcohol enters the bloodstream and reaches the brain, it binds to certain neurotransmitters (substances that facilitate communication between nerve cells) like gamma-aminobutyric acid (GABA) and glutamate.

This slows the communication between brain cells and has a calming effect on the mind and body. This is why you might feel relaxed and as though your stress and tension are melting away when drinking alcohol. It's also why alcohol can make you feel sleepy or drowsy, especially as your blood alcohol concentration rises.

Euphoria or Giddiness

Alcohol consumption can sometimes lead to feelings of euphoria or giddiness. As alcohol enters the bloodstream and reaches the brain, it prompts the release of dopamine and serotonin—two neurotransmitters associated with pleasure, reward, and happiness.

By promoting the release of these feel-good neurotransmitters, alcohol temporarily amplifies feelings of joy and lightheartedness.

Changes in Mood

While alcohol can initially boost your mood, these effects are temporary and wear off quickly. Alcohol impairs the brain's ability to regulate emotions, and mood changes are common. As the night wears on, you may notice your cheerful feelings soon begin to shift to irritability, sadness, aggression, or anxiety.

Alcohol's impact on neurotransmitters like serotonin and GABA can also contribute to mood changes the day after drinking. Once the effects of alcohol wear off, glutamate (a neurotransmitter) levels increase, which can lead to feelings of depression and anxiety, or "hangxiety" (hangover and anxiety), the day after drinking.

Lowered Inhibitions

One of the best-known effects of drinking alcohol is lowered inhibitions. Alcohol disrupts the brain's prefrontal cortex—the area responsible for judgment and self-control. When drinking alcohol, you may become less cautious and more likely to engage in behaviors and take risks you wouldn't consider when sober.

For example, a usually shy and quiet person may become increasingly chatty, socially confident, and outgoing when drinking alcohol. Lowered inhibitions can also lead to poor decision-making and increase the risk of engaging in risky behaviors.

Impulsive Behavior

Lowered inhibitions when drinking alcohol can lead to impulsive behavior—engaging in behaviors without considering the potential consequences of your actions. The impairing effects of alcohol on cognitive functioning—including concentration, thinking, reasoning, and decision-making—play a role in increased impulsivity while drinking.

Impulsive behaviors can include making poor financial decisions (e.g., spending rent money on a round of drinks for your friends) or engaging in risky sexual behaviors (e.g., condomless sex).

Alcohol intoxication also is associated with an increased risk of suicide because lowered inhibitions and mood changes can lead to suicidal ideation (thoughts or ideas about suicide) and increase the likelihood of impulsively acting on these thoughts.

Slowed or Slurred Speech

Alcohol slows signals from the brain to the muscles responsible for the coordination and control of muscles involved in speech, leading to a noticeable slowing down or slurring of words when intoxicated.

Alcohol's impact on cognitive functioning can also make it challenging for people drinking alcohol to form and verbally express coherent thoughts.

Nausea and Vomiting

Alcohol increases the production of stomach acids and can lead to reflux (stomach acids backing up into the esophagus and the throat). Alcohol also irritates the stomach lining, leading to inflammation (gastritis), which can make you feel nauseated and throw up. 

Your liver breaks down alcohol and converts it into a toxin and known carcinogen called acetaldehyde. When you drink large amounts of alcohol or drink more quickly than the liver can metabolize it, alcohol accumulates in your bloodstream, triggering vomiting.

Diarrhea

Alcohol causes irritation and inflammation along your gastrointestinal (GI) tract, disrupting normal digestive function. Evidence suggests that certain alcoholic beverages, such as wine and beer, appear to accelerate the movement of food and waste through the digestive system, which can lead to diarrhea.

Alcohol can also disrupt the balance of bacteria in your gut microbiome (the community of microbes that live in your digestive tract), leading to an overgrowth of certain bacteria that contribute to GI inflammation and diarrhea.

Headache

Getting a headache is a common experience after drinking too much alcohol. A combination of factors can contribute to alcohol-induced headaches, including the following:

• Alcohol is a vasodilator, meaning it opens (dilates) blood vessels and increases blood flow to the brain, which may contribute to headaches.
  

• Alcohol is a diuretic, meaning it increases urine production and the loss of fluids and electrolytes in the body, leading to dehydration-related headaches.

• Alcohol contains compounds called congeners, which are byproducts of alcohol fermentation or distillation. Evidence suggests that darker-colored drinks like red wine and whiskey contain higher amounts of congeners, which may trigger headaches in some people.

Changes in Vision, Hearing, and Perception

Alcohol disrupts the communication between the brain and sensory organs (e.g., eyes and ears), leading to changes in vision, hearing, and perception of the sounds and sights around you.

Alcohol can disrupt the transmission of auditory signals from the ears to the brain and increase blood flow to the ears, resulting in tinnitus (ringing in the ears), difficulty distinguishing sounds, and trouble perceiving subtle differences in pitch or tone.

Excessive drinking also commonly causes vision changes, such as blurred vision, double vision, or difficulty focusing. Alcohol impairs the signals from the eyes to the brain and affects the muscles that control eye movement, leading to weakened eye-muscle control and decreased peripheral vision (seeing to your left and right sides).

Loss of Coordination

Loss of coordination (ataxia) is a common short-term effect of alcohol and is linked to how alcohol affects the brain's cerebellum. The cerebellum is the brain's control center for movement, balance, and coordination.

Alcohol impairs the cerebellum's ability to process information and coordinate muscle movements effectively, leading to a loss of balance, unsteady gait (manner of walking), and difficulty performing fine motor skills (e.g., grasping).

Trouble Focusing or Making Decisions

Alcohol disrupts the brain's functioning in several ways, leading to trouble focusing and making decisions. Because alcohol is a depressant, it disrupts normal brain functions, making it harder to concentrate on tasks that require focused attention.

The frontal cortex is the brain's center for higher-order functions like planning, decision-making, and impulse control. Alcohol disrupts frontal cortex functioning, leading to poor judgment, difficulty weighing options logically, and increased impulsivity.

Alcohol also impairs working memory, making it harder to keep track of details, follow instructions, and complete complex tasks that require ongoing mental processing.

Loss of Consciousness or Gaps in Memory

After a night of drinking, you may have gaps in memory, in which you recall some details from a situation or event but forget others. Alcohol's impact on memory and consciousness is based on its effect on the hippocampus, the part of the brain that controls memory and learning.

When you consume alcohol, the effects of alcohol on the hippocampus make the formation of long-term memories less likely. Alcohol-related blackouts (gaps in your memory while drinking alcohol) can occur because alcohol hinders the ability of the hippocampus to transfer short-term memory to long-term storage in the brain.

Hangover

While the short-term mood-boosting effects of alcohol can be enjoyable for some, they often come with a price: a hangover. A hangover is a set of unpleasant symptoms that can occur after consuming too much alcohol, including:

• Anxiety

• Fatigue

• Headache

• Increased blood pressure

• Irritability

• Nausea

• Sensitivity to light and sound

• Stomach cramping

• Sweating

• Thirst

• Vertigo (a dizzying sensation of spinning or motion)

• Weakness
  

Several factors can contribute to a hangover, including:

• Acetaldehyde exposure: The toxic acetaldehyde that is produced when the body breaks down alcohol can contribute to inflammation and hangover symptoms.

• Dehydration: Because alcohol is a diuretic, it can cause excessive urination and loss of fluids.

• Disrupted sleep: While alcohol may initially make you tired, it disrupts sleep quality throughout the night. This can lead to feelings of fatigue, grogginess, and difficulty performing daily tasks.

• Gastrointestinal irritation: Alcohol irritates the lining of the gastrointestinal tract, increasing stomach acid amounts and leading to nausea, vomiting, and discomfort.

• Inflammation: Alcohol can trigger low-grade inflammation throughout the body, contributing to hangover symptoms.

Alcohol Poisoning

Alcohol poisoning, or alcohol overdose, occurs when you drink more than your body can handle. Your BAC increases to the point that it disrupts areas of the brain controlling essential functions like heart rate, breathing, and temperature control.

Symptoms of alcohol poisoning include:

• Cold, clammy skin

• Confusion

• Difficulty breathing

• Dulled reflexes (e.g., no gag reflex)
  

• Loss of consciousness
  

• Seizures

• Slowed heart rate

• Vomiting
  

Alcohol poisoning can quickly become life-threatening and requires prompt medical treatment. Call 911 for help if you suspect someone is experiencing alcohol poisoning. Symptoms can vary from person to person, so it's best to exercise caution and seek medical help if someone you are with shows signs of extreme alcohol intoxication.

Summary

The short-term effects of alcohol develop quickly—within minutes after your first drink—impacting mood, coordination, speech, memory, and behavior.

While many people who drink alcohol initially experience relaxation or euphoria, these feelings are temporary. Negative emotions, poor judgment, and changes to your vision, hearing, coordination, and memory-making abilities often follow.

Alcohol disrupts normal brain function, leading to lowered inhibitions, impulsive behavior, and difficulty focusing or making decisions.

Binge drinking (drinking excessive amounts) and drinking too quickly can trigger unpleasant symptoms that occur the night of or the day after drinking, including headaches, diarrhea, dehydration, nausea, and vomiting. Drinking too much or too quickly can lead to alcohol poisoning. This is a potentially life-threatening situation that requires immediate medical attention.

If you choose to drink alcohol, drink responsibly. This means pacing yourself, eating before drinking, knowing your limits, and avoiding excessive consumption. 

Read the original article on Verywell Health.