A protective cap for a dispenser for discharging liquids, wherein the dispenser has a liquid reservoir and an outlet opening through which the liquid is discharged into a surrounding atmosphere. The protective cap has an inner cap and an outer cap, the inner cap having a ventilation opening for communication between an interior of the protective cap and an external environment. Before use, the outer cap is mounted on the inner cap in a first position with the inner cap and the outer cap in sealing contact with each other and the ventilation opening is separated in an airtight and germproof manner from the environment, and the outer cap is movable relative to the inner cap from the first position to a second position in which the inner and outer caps are out of sealing contact with each other and the ventilation opening communicates with the environment.