This term is often applied to skin care products like lotions, cleansers, sun creams and oils to describe whether or not they will block the pores. ‘Comedo’ is a type of pimple and is used to describe the least severe form of acne. If something is comedogenic, it means that it contains ingredients that will block the pores and this could lead to blemishes and acne.
If something is non-comedogenic, it is safe to use on oily and acne prone skins, as it won’t block the pores and cause more problems. Non-comedogenic products are generally oil free.