How Does Hand Sanitizer Kill Bacteria?


Disease-causing germs are present around you all the time. One main route of infection for these pathogens is your hands. Your hands are constantly touching the environment around you, picking up pathogens as they go, allowing these harmful substances to infect you or spread to others. To prevent this, the Center for Disease Control and Prevention recommends the regular washing of your hands with soap and water 1. Unfortunately, clean water and soap is not always available. In these cases the CDC recommends using an alcohol-based hand sanitizer, which is capable of killing most germs.

Active Ingredients

Most hand sanitizers' active ingredients consist of either ethanol or isopropanol, both forms of alcohol. Alcohol kills most germs on contact without causing serious harm to the skin tissue, which makes it an effective active ingredient for hand sanitizers. Ethanol and isopropanol are antiseptics that kill germs by dissolving their essential proteins. This disrupts the normal cell activity of the germ, causing it to die.

Inactive Ingredients

To aid in application, and increase the skin benefits of the product, hand sanitizers often use inactive ingredients alongside ethanol or isopropanol. For example, humectants, such as glycerin, work as moisturizing agents. Humectants draw moisture from the surrounding environment and hold it close to the skin. Thickening agents, such as polyacrylic acid, may also be used to give hand sanitizers a gel like texture, which aids in the application and spreading of the product on the hands. A newer development in hand sanitizers is the use of fragrance oils to help lessen the smell of alcohol when applying the product.


Hand sanitizers with at least a 60 percent inclusion of alcohol are effective in killing bacteria, including the Streptococcus bacteria, as well as the bacteria that cause tuberculosis (TB). Hand sanitizers are also effective against fungal infections, as well as enveloped viruses, such as the common cold and flu viruses.