Alcohol kills some viruses, but not all. The effectiveness depends on the concentration and type of alcohol, along with the species of the virus.

Although the Centers for Disease Control and Prevention (CDC) recommend washing the hands with soap and water, this mode of cleansing is not always available. When it is not, using alcohol-based hand sanitizers can help prevent transmission of viral infections, including SARS-CoV-2, the virus that causes COVID-19.

As well as using sanitizers to cleanse the hands, people can use rubbing alcohol to disinfect frequently touched objects in the home, such as phones and computer keyboards.

This article discusses how well alcohol can kill viruses, how it works, and what concentrations to look for. It also provides instructions on how to use hand sanitizers and rubbing alcohol.

A person wearing rubber gloves while wiping alcohol spray onto a door to kill viruses.Share on Pinterest
Charday Penn/Getty Images

According to a 2020 study, both isopropyl alcohol and ethyl alcohol can kill an array of viruses. Isopropyl alcohol is the main ingredient in rubbing alcohol, while ethyl alcohol is the type of alcohol present in alcoholic beverages.

The efficacy of these alcohols depends on their concentration and the type of virus. Enveloped viruses have a lipid membrane, while nonenveloped viruses are those without a lipid membrane. Generally, nonenveloped viruses are more resistant to disinfectants.

Isopropyl alcohol works against enveloped viruses but not against nonenveloped viruses. Ethyl alcohol works against enveloped viruses and a few nonenveloped viruses. Both ethyl and isopropyl alcohol have potent antiviral action against:

These alcohols do not have antiviral action against nonenveloped viruses, such as polio and hepatitis A.

Few studies have looked at how alcohol kills viruses. However, scientists believe alcohol disrupts the cell membrane of the virus by changing the structure of its proteins. A 2021 article refers to this process as “denaturing and coagulation.” Without a functional membrane, the virus cannot reproduce and cause infection.

Adding water to alcohol makes it more effective in denaturing the proteins. This is because alcohol on its own evaporates very quickly. Water slows this down, exposing viruses to the alcohol for longer.

SARS-CoV-2 is the virus responsible for the COVID-19 pandemic. Since the outermost membrane of SARS-CoV-2 contains lipids, alcohol is effective against it.

A 2020 study found that certain concentrations of ethyl or isopropyl alcohol rendered the virus inactivate after 30 seconds. The CDC advises using alcohol-based hand sanitizers to prevent SARS-CoV-2 transmission when soap and water are not available.

A 2021 research article states that the recommended concentration of alcohol in sanitizers is 80% ethyl alcohol or 75% isopropyl alcohol. However, sanitizers containing at least 60% alcohol are also effective, according to the CDC.

The 2020 study that evaluated the impact of hand sanitizer formulations on SARS-CoV-2 found that concentrations higher than or equal to 30% resulted in complete viral inactivation.

People can use alcohol-based sanitizers or rubbing alcohol around the home to clean small objects and high touch surfaces, such as phones or door handles. To clean these items, first:

  1. Ensure the room has good ventilation.
  2. Apply rubbing alcohol to a cotton pad.
  3. Replace the cap to avoid inhalation.
  4. Wipe the pad over the surface.
  5. Dispose of the cotton pad safely.

The National Capital Poison Center warns that rubbing alcohol has certain dangers. Even small amounts are toxic if a person inhales the fumes or drinks any quantity of it. To reduce the risk, a person should:

  • store rubbing alcohol securely out of the reach of children
  • only use it in well-ventilated rooms
  • keep away from open flames
  • never swallow rubbing alcohol

If someone has come into contact with a toxic substance, take action immediately. First, reduce harm in one of the following ways:

  • For swallowed poison: If a person is experiencing burning or irritation and they are conscious, not having convulsions, and able to swallow, help them drink a small amount of water or milk.
  • For poison in the eye: Remove contact lenses and rinse the eye immediately under a running faucet for at least 15–20 minutes. Adults or older children may find it easier to rinse eyes in the shower.
  • For poison on clothing: Remove the contaminated clothing immediately and rinse the skin under running water.
  • For inhaled poison: Get to fresh air and stay away from the toxic fumes or gases.

    Next, contact Poison Control, or ask someone else to do this. There are two methods:
  • call Poison Control at 1-800-222-1222
  • use the POISONCONTROL tool

    Both options provide free, expert advice on what to do in a given situation and are available 24–7.

    Do not try to treat poisoning at home with ipecac syrup, charcoal, or other home remedies. These substances can be ineffective or even harmful.

There are two ways to use alcohol on the skin to kill viruses. The first is using alcohol-based hand sanitizer gel. People can use this by applying some gel to the palms and rubbing all over the hands, including between the fingers. Then, wait until it dries.

Doctors no longer recommend that people use rubbing alcohol to clean wounds, as it can further damage tissue. Instead, a person can rinse the wound under running tap water for 5–10 minutes before soaking a gauze pad in saline solution or tap water and gently dabbing or wiping the skin with it. Alternatively, they can use an alcohol-free wipe.

While alcohol gels and sterilizing products effectively kill a number of potentially harmful microbes, they have some disadvantages.

Inferior to washing with soap and water

The CDC advocates washing hands with soap and water whenever possible. Unlike hand sanitizers, soap and water can remove all kinds of germs from the hands. This includes all types of bacteria, viruses, and other substances, such as pesticides.

In some situations, washing the hands with soap and water is necessary for proper hygiene. These include:

  • before, during, and after food preparation
  • after using the toilet
  • after touching garbage
  • when the hands are visibly greasy or dirty
  • before and after caring for a person who is sick
  • before and after visiting someone with a weakened immune system

If soap and water are not available, use a sanitizer that contains at least 60% alcohol.

Inferior to other surface cleaners

Alcohol is less effective than some other disinfectants for cleaning surfaces or equipment. For example, in hospitals, staff typically opt for hydrogen peroxide or other disinfectants instead of alcohol to clean surroundings, such as floors.

These substances can kill a wider variety of microbes than alcohol and do not evaporate as quickly, meaning they are in contact with the microbes for longer. However, they have their own pros and cons and have not entirely replaced alcohol.

The fast evaporation of alcohol can be an asset when disinfecting noninvasive equipment, such as thermometers. Additionally, unlike hydrogen peroxide, alcohol does not discolor clothes and fabrics.

Antibiotic resistance

Alcohol-based sanitizers have antibacterial properties in addition to their antiviral ones. However, bacteria can evolve over time so that substances no longer harm them. This is known as antibiotic resistance.

Some researchers have concerns that hand sanitizers may contribute to antibiotic resistance. However, a 2021 research article reports that alcohol has not shown the potential to cause bacterial resistance.

Certain experts advise cleaning the hands with sanitizer for a full 20–30 seconds and allowing it to dry to reduce the chance of leftover bacteria evolving resistance.

Both isopropyl and ethyl alcohol can kill viruses that have cell membranes with high lipid content. SARS-CoV-2 fits into this category, along with HIV, the hepatitis B virus, and herpes viruses. Alcohol works by changing the structure of the viral membrane, making it unable to function.

Washing the hands with soap and water is superior to using alcohol-based sanitizers. However, when this option is not available, people can use hand gels containing 60–90% alcohol. The optimal concentrations are 80% ethanol or 75% isopropyl alcohol.

People can also use rubbing alcohol to clean small items around the home, but it is important to follow precautions while handling it.