Does Hand Sanitizer Work? + How To Use It, According To Doctors
One of the most common pieces of advice when it comes to preventing the spread of COVID-19 is to practice good hand hygiene. The Centers for Disease Control (CDC) recommends using hand sanitizer when soap and water are not available. But does hand sanitizer actually even work or is it just drying out our hands?
To find out, mbg spoke with immunologist Heather Moday, M.D. and integrative medicine doctor Amy Shah, M.D.. They share how effective hand sanitizer can be, how to properly use it, and what ingredients to look for.
Does hand sanitizer work?
According to Moday, hand sanitizer does not replace good hand-washing. "If hands are soiled or have come in contact with any toxins or pesticides, washing with good old soap and water is the best way to go," she says. However, when soap and water are not available, hand sanitizer is the next best option.
Some major bugs that can't be killed by hand sanitizers include Clostridium difficile, or C. diff., Norovirus, and MRSA, Moday says. It may be too soon to tell if hand sanitizer can kill SARS-CoV-2 (the virus that causes COVID-19), but research has been promising.
One study published by the CDC says alcohol-based hand sanitizers may inactivate the virus. In order to be effective, the hand sanitizer was actively rubbed into the skin for at least 30 seconds.
How to properly use hand sanitizer.
When using hand sanitizer, the CDC says to:
- Apply it to the palm of one hand.
- Rub your hands together.
- Continue rubbing the hand sanitizer until it completely covers the hands and fingers.
- Rub until hands are dry.
According to the study above, this process should take 30 seconds to be fully effective. After sanitizing, Shah recommends applying moisturizer. Hand sanitizer can be quite harsh and drying on the hands, she says.
What to look for in a hand sanitizer.
According to Moday, most hand sanitizers contain rubbing alcohol (also called isopropyl alcohol) or ethyl alcohol. Hand sanitizers with 60% or more of these ingredients have been shown to reduce and kill most bacteria and viruses, she explains.
Many will also have emollients (aka moisturizers) and small traces of water. This is because alcohol tends to be drying, which can weaken the skin barrier, Moday explains. Water will allow sanitizer to better penetrate the skin and reach the viruses they're trying to kill.
Herbal alternatives have not been proven to be as effective. "Many of the constituents in natural sanitizers such as lavender, witch hazel, or thyme have some antimicrobial benefits," Moday says, "but there are no studies showing they effectively kill bad germs on your hands."
Washing hands with soap and water should always be first priority, but when the option is not available, hand sanitizer should be used. In order to be effective, hand sanitizer should contain at least 60% alcohol and should be applied for a full 30 seconds.