The average Benzoyl peroxide cash price is about $14.87 for a supply of: Gel 5 % 30 pcs. Get our free Benzoyl peroxide coupon and be eligible to receive a discount. You can reduce your Benzoyl peroxide cost by up to 75% with our free Benzoyl peroxide discount card. Bring it to a participating pharmacy near you to save on your prescription medication.Benzoyl peroxide has an antibacterial effect. It also has a mild drying effect, which allows excess oils and dirt to be easily washed away from the skin. Benzoyl peroxide topical (for the skin) is used to treat acne. There are many brands and forms of benzoyl peroxide available and not all brands are listed on this leaflet. Benzoyl peroxide topical may also be used for purposes not listed in this medication guide.