What is the effect of anaphoresis on the skin?

Anaphoresis is a process used in facial treatments where a negative electrical current is applied to the skin, resulting in the opening and expansion of the pores. This technique allows for the deep penetration of water-soluble products into the skin, enhancing their effectiveness. The primary goal of anaphoresis is to facilitate the delivery of beneficial ingredients into the deeper layers of the skin while also promoting a cleanse that helps to remove impurities.

The option that states "open and expands the skin" accurately captures the physiological effect of anaphoresis by emphasizing its role in dilating the pores, making it easier for products to enter the skin. This process is particularly beneficial in preparing the skin for further treatments or product applications, as it can create a more receptive state for skincare.

Other options like closing and tightening pores are more reflective of the process known as cataphoresis, which involves a different current application that constricts pores. Reducing redness or hydrating the dermis may be secondary effects of other techniques or products but do not accurately describe the primary action of anaphoresis.