Slugging: What It Is, How to Do It, and Who It's For

Slugging is the viral-sounding habit of sealing your skincare under a layer of a thick, occlusive product overnight. Behind the odd name is a genuinely useful technique for dry, dehydrated and barrier-stressed skin — though it isn't for everyone. Here's how it works and who should (and shouldn't) try it.

What is slugging?

Slugging means applying a thin layer of an occlusive — most often a simple petrolatum-based ointment — as the very last step of your evening routine. An occlusive doesn't hydrate the skin itself; it forms a seal that dramatically slows water loss overnight, so the hydrating layers underneath work harder and skin wakes up softer and more comfortable. The name comes from the slightly shiny, slug-like sheen it leaves.

Who is slugging for?

• Dry and dehydrated skin — the main audience; sealing in moisture overnight is exactly what parched skin needs. See how to fix dehydrated skin.
• Compromised or stressed barriers — after over-exfoliating, winter weather or flights, slugging gives the barrier a protected environment to recover. See how to repair a damaged skin barrier.

How to slug safely

• Cleanse, then apply your usual hydrating serum and moisturiser to slightly damp skin — the occlusive seals in whatever is underneath, so you want water and humectants there first.
• Finish with a thin layer of occlusive. A little goes a long way.
• Do it in the evening, and use an old pillowcase — it can transfer.
• A couple of nights a week is plenty for most; you don't need to do it nightly.

Crucially, never slug over active ingredients like retinoids or exfoliating acids — sealing them in amplifies their effect and can cause irritation. Save those for other nights.

Who should skip it

Slugging isn't for everyone. If your skin is oily, congestion-prone or acne-prone, sealing everything in can trap oil and trigger breakouts — so it's best avoided or limited to drier patches. It's also not the step that hydrates; without a humectant and moisturiser underneath, you're just sealing dry skin. Think of it as the lid, not the drink.

Slugging FAQs

What is slugging in skincare?

It's applying a thin layer of an occlusive product, usually petrolatum-based, as the final evening step to seal in your skincare and slow overnight water loss. It leaves skin softer and more comfortable by morning.

Does slugging actually work?

For dry, dehydrated or barrier-stressed skin, yes — sealing in hydration overnight is genuinely effective. It works best over a hydrating serum and moisturiser, since the occlusive locks in moisture rather than adding it.

Who should not slug?

Oily, congestion-prone and acne-prone skin should avoid or limit it, as sealing everything in can trap oil and trigger breakouts. Never slug over retinoids or acids, which can become irritating when sealed in.

How often should I slug?

A couple of nights a week is enough for most people, especially in dry weather or after your barrier has been stressed. Nightly isn't necessary.

What can I use for slugging?

A simple, fragrance-free petrolatum-based ointment is the classic choice. Apply a thin layer over your usual hydrating serum and moisturiser on slightly damp skin.