How do topical retinoids function in the treatment of acne?

Topical retinoids play a crucial role in the treatment of acne primarily by affecting the terminal differentiation of the follicular epithelium. They work by promoting the normal turnover of skin cells in the hair follicles. In acne, there is often a disruption in this process, leading to the improper shedding of dead skin cells and the consequent formation of comedones (clogged pores). By enhancing cell turnover and ensuring that cells shed properly, topical retinoids help to prevent the formation of these blockages, thereby reducing acne lesions.

Unlike other treatments, topical retinoids do not directly decrease oil production in sebaceous glands or eliminate bacteria from the skin, which are mechanisms associated with other types of acne treatments such as topical antibiotics or systemic therapies. They also do not primarily function by tightening the skin or reducing pore size, although some patients may perceive an improvement in skin texture and appearance as a secondary benefit.

Thus, their efficacy lies in their ability to normalize the follicular epithelial turnover, making them a key component in managing and treating acne effectively.