As people concerned about the coronavirus continue snatching up hand sanitizer, retail outlets have been having a difficult time keeping their shelves stocked with the germ-killing hand solution. But there's no need to worry; experts say homemade hand sanitizer is every bit as effective as store-bought versions. The active ingredient in hand sanitizer is something most people already have in their bathrooms: rubbing alcohol, says Dr. David Agus. Combine 2/3 cup rubbing alcohol with 1/3 cup aloe vera gel. Adding several drops of essential oil will make it smell better, but it's not necessary, Agus says. Then mix it up and it's ready. While hand sanitizer doesn't kill all viruses, it's been proven to be effective against the coronavirus, Agus says.