Slugging is the trend of finishing your night routine with a thin layer of an occlusive — petrolatum (Vaseline), Aquaphor, or a balm — as the very last step, to seal everything underneath and stop water escaping while you sleep. You wake up plumper and calmer.
Why it works
Occlusives don't hydrate — they trap. Sealed in, your moisturiser and humectants can't evaporate overnight (less transepidermal water loss), so a dry or compromised skin barrier gets a real chance to recover. That's why slugging shines for dry skin, cold weather, and barriers that have been over-exfoliated.
How to do it
- Cleanse.
- Layer your hydration: a humectant (hyaluronic acid) and a ceramide-rich moisturiser.
- Finish with a thin layer of occlusive. PM only.
Who should skip it — and the one rule everyone forgets
- Acne-prone or oily skin: occlusives can trap oil and congestion, so slug sparingly (if at all) and only over bare, hydrated skin.
- Never slug over actives. Sealing in a retinoid or an acid amplifies how much penetrates — a fast track to irritation. Slug on your recovery nights, not your active nights. (This is exactly why skin cycling pairs so well with slugging — slug on the rest nights.)
Fit it into your routine
Slugging is a finishing move, not a routine on its own. Build your PM routine first, and use slugging on the nights you're not exfoliating or retinoid-ing.