What is a slugging routine?

Slugging is a Korean beauty practice of applying a thin layer of petrolatum-based occlusive (like Vaseline) as the final step of your nighttime routine to form a seal that prevents transepidermal water loss while you sleep. It dramatically improves dry and dehydrated skin overnight. It is not suitable for acne-prone skin, as petrolatum can trap debris and sebum in congested pores, but it is highly effective for dry, flaky, or barrier-damaged skin.