How come many mouthwashes use alcohol?

Killing germs: Many mouth rinses do contain alcohol but not more are coming out without alcohol so you have options. Make sure you check labels and ask your dentist for correct mouth rinse.

It's a disinfectant: Alcohol has historically been used as a disinfectant; listerine is a well known example whose original formulation was 27% alcohol. Today there are a number of good non alcohol mouth rinses that are also effective and gentle. Crest prohealth, colgate total, natural dentist and listerine zero are a few.