In dermatology, a facial steamer is used to prepare the skin for treatments by opening pores, which allows for a deeper cleanse to remove dirt, oil, and sebum. The steam also boosts blood circulation, which can help with collagen production, improve skin elasticity, and increase the absorption of skincare products. While it can be beneficial for unclogging pores and can be a helpful part of acne treatment, it can worsen conditions like rosacea or eczema and should be used with caution in sensitive skin.