I like chlorhexidine gluconate 0.12 oral rinse, which is a prescription mouth wash. It can stain your teeth over long-term use though, so if you want a safe option that doesn't stain your teeth and improves bad breath, then Oracare is a great option. When choosing your OTC mouth wash, choose from the alcohol-free ones.

There are several types Chlorhexidine Gluconate and Chlorine Dioxide mouth rinses work well. Food-Grade Hydrogen Peroxide diluted with water 50:50 rinses are secondary to proper brushing and flossing.

Over the counter, use Listerine or hydrogen peroxide cut 50/50. Peridex is a good one too, but requires a prescription!

Saline [salt water] plus baking soda is the research standard. A good alcohol-free essential oil such as the Dental Herb Company's products are more effective than even chlorhexidine products without the toxic downsides.