Alcohol has a variety of effects on the immune system and can make people more susceptible to infections and other health conditions, including COVID-19.

Does Alcohol Weaken the Immune System?

Alcohol abuse can suppress your immune system, making you more vulnerable to infections caused by bacteria and viruses which might raise your risk of a bacterial infection such as urinary tract infections (UTIs). The immune system is complex and made of many cells and proteins that recognize infections and attack them. Often, the immune system takes time to recognize and build up a full response to an infection. This is why when you get an infection, you will often have symptoms that get worse as the infection develops. Then, you’ll get better as the immune system response becomes strong enough to stop and remove the infection.

Because alcohol can suppress the immune system, the body may take longer to recognize and respond to a developing infection. This can make infection symptoms last longer and become more intense than they would otherwise. In severe cases, the body’s immune system may not be strong enough to overcome the infection. When this occurs, the infection may continue to develop until it becomes dangerous or is treated with antibiotics.

Short-Term Effects of Alcohol on the Immune System

Many tend to think that alcohol-induced damage to the immune system only occurs in people who use large amounts of alcohol for a long time. However, this is not the case. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) warns that a single episode of drinking can suppress the immune system for up to 24 hours. Additional studies continue to show that drinking, even once, can suppress the immune system afterward for a short time.

Long-Term Changes in the Immune System of an Alcoholic

Alcohol use over prolonged periods of time will create long-term immune system problems. While alcohol’s actual effects on the immune system are complex at a chemical and cellular level, chronic alcohol use has been shown to affect every area of the immune system. It significantly increases the risk of developing infections, even causing infections that a healthy person would not normally be at risk for.

In addition to suppressing every area of the immune system, these long-term changes may also cause the immune system to create inflammation when it normally would not. This can lead to other unpleasant effects and cause discomfort or medical problems.

How Much Alcohol Is Too Much?

The NIAAA defines heavy drinking as consuming more than three drinks per day for women or more than four per day for men. Still, even moderate drinking can have a negative effect on immune system health. Some research suggests that using light amounts of alcohol may have positive effects on immune health; however, this research is controversial and has not been well proven.

Ultimately, the best way to prevent alcohol from affecting the immune system is to avoid using alcohol altogether. However, light drinkers (defined as less than one drink a day for women or less than two drinks a day for men) may be less likely to experience negative immune system effects than those who drink heavily.

Related: Am I an Alcoholic? Take the Quiz

Does Binge Drinking Suppress Your Immune System More?

Binge drinking does suppress your immune system more. Because a larger dose of alcohol is used, the effects of a single episode of drinking will be most evident when someone binge drinks. A single episode of binge drinking can greatly reduce immune system function for up to 24 hours.

While alcohol can certainly lead to immune system suppression, it can also lead to many other diseases and conditions. Some of the negative health effects of alcohol use include:

  • High blood pressure
  • Heart disease
  • Stroke
  • Liver disease
  • Digestive problems
  • Many types of cancers
  • Infectious disease
  • Learning and memory problems
  • Dementia
  • Alcohol use disorder

While this list highlights several medical conditions, it is only a partial list. There are many other conditions that alcohol can cause, such as lung and kidney problems and an increased risk of injury.

We surveyed 2,136 American adults who either wanted to stop drinking alcohol or had already tried to (successfully or not).

When we asked asked participants about health complications directly related to their alcohol use:

  • 1 in 3 reported depression (38%)
  • 1 in 3 reported high blood pressure (31%)
  • 1 in 6 reported liver disease (17%)
  • 1 in 10 reported cirrhosis (scarring of the liver) (12%)
  • 1 in 10 reported cardiovascular disease (11%)
  • 1 in 7 reported a weakened immune system (15%)
  • 1 in 10 reported nerve damage (11%)
  • 1 in 12 reported pancreatitis (8.4%) 1 in 11 reported seizures (9%)
  • 1 in 13 reported cancer (7.8%)

Infectious Diseases

Because alcohol suppresses the immune system, it increases the risk of getting infectious diseases. It also makes it harder to recover once you do have an infection. The two most serious infectious diseases that may be associated with alcohol use include HIV and hepatitis C. Both of these conditions tend to be caught through use of IV needles or unprotected sex, but alcohol lowers inhibition and impairs judgment. Alcohol makes risky situations more likely, and its effects on the immune system increase the risk of catching these infections.

Lung Diseases

Alcohol can lead to lung diseases, especially pneumonia. Pneumonia is a lung infection that occurs when bacteria or viruses enter the lungs. The immune system responds to pneumonia by flooding the infected area of the lungs with fluid and immune cells. While this response is necessary to overcome the infection, it can be dangerous and essentially cause someone to drown. Antibiotics often provide the best chance of surviving pneumonia.

Since alcohol use suppresses the immune system, it makes the body less able to fight against lung infections. Alcohol also makes the body take longer to fight off a pneumonia infection.

Alcohol also impairs the inner lining of the lung, making it harder for the lungs to get rid of bacteria or viruses that could cause pneumonia. Alcohol use can also cause vomiting, and someone who is intoxicated may accidentally inhale their vomit. This makes it even more likely that someone could get pneumonia while drinking.

Drinking and COVID-19

COVID-19 is a viral infection. Though little research has been done on how alcohol use affects the risk of COVID-19, it seems likely that someone who uses alcohol would be more likely to catch it.

Alcohol use, especially chronic use, raises pneumonia and inflammation risks. Two of the biggest complications with COVID-19 include pneumonia and a cytokine storm, a type of inflammatory condition. These two complications are most often the difference between a mild course of COVID-19 and a potential fatality. Though research is limited because this disease is so new, it does seem likely that alcohol use could lead to an increased likelihood of fatal COVID-19 complications.

The pandemic’s effects of boredom, stress and isolation have also led to an increase in alcohol use and alcohol addiction. Many people who have never struggled with alcohol use before are finding themselves drinking more and more at a time when promoting optimal immune health is incredibly important.

How To Repair and Support the Immune System After Drinking

Once someone stops using alcohol, healing will often focus on promoting the best immune health possible. Harvard Health Publishing recommends several simple ways to improve immune system health:

  • Avoid smoking
  • Follow a diet that is high in fruits and vegetables
  • Get sufficient sleep
  • Exercise regularly
  • Maintain a healthy weight
  • Reduce stress when possible
  • Follow good hygiene

In the context of the ongoing pandemic, following health hygiene rules and guidelines from the Centers for Disease Control and Prevention and local health departments will also be important.

While these tips can promote immune system health, the best tip for healing the immune system is to stop drinking alcohol as soon as possible. If you are struggling to stop using alcohol, The Recovery Village is here to help. Contactone of our caring team members today to learn more about treatment programs that can work well for you.

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Editor – Jonathan Strum
Jonathan Strum graduated from the University of Nebraska Omaha with a Bachelor's in Communication in 2017 and has been writing professionally ever since. Read more
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Medically Reviewed By – Benjamin Caleb Williams, RN
Benjamin Caleb Williams is a board-certified Emergency Nurse with several years of clinical experience, including supervisory roles within the ICU and ER settings. Read more

National Institute on Alcohol Abuse and Alcoholism. “Alcohol’s Effects on the Body.” 2020. Accessed October 23, 2020.

Szabo, Gyongyi; Saha, Banishree. “Alcohol’s Effect on Host Defense.” Alcohol Research: Current Reviews, 2015. Accessed October 23, 2020.

U.S. Centers for Disease Control and Prevention. “Alcohol Use and Your Health.” October 1, 2020. Accessed October 23, 2020.

Kershaw, Corey; Guidot, David. “Alcoholic Lung Disease.” 2008. Accessed October 23, 2020.

Sarkar, Dipak; Jung, Katherine; Wang, Joe. “Alcohol and the Immune System.” Alcohol Research: Current Reviews, 2015. Accessed October 23, 2020.

National Institute on Alcohol Abuse and Alcoholism. “Drinking Levels Defined.” Accessed October 23, 2020.

Harvard Health Publishing. “How to boost your immune system.” April 6, 2020. Accessed October 23, 2020.

Medical Disclaimer

The Recovery Village aims to improve the quality of life for people struggling with substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare providers.