Acnecide Gel Benzoyl Peroxide 5% (60g). Acnecide is used in the management of acne vulgaris.. Before each application, the skin should be cleaned and dried. Apply in a thin layer once or twice daily or as directed to the affected areas.. Persons with sensitive skin should be directed to apply the gel once daily before going to bed. The extent of any drying or peeling may be adjusted by modifying the dosage schedule.