Slugging and Occlusives: What Sealing Your Skin Actually Does

July 1, 2026

Slugging, the habit of sealing your skin with an occlusive layer overnight, went viral for good reason. The underlying idea, holding moisture in, is well established.

What occlusives do

Occlusives form a layer over the skin that slows water loss to the air. Classic research on petrolatum, a well known occlusive, examined its effects on the outer skin and its role in reducing water loss and supporting barrier recovery (Ghadially et al., 1992, PMID 1564142). By holding water in, occlusives give the skin barrier a better environment to repair.

Who slugging suits

Dry, dehydrated or wind-chapped skin that needs help holding moisture.
Use over a hydrating serum or moisturiser, so there is water to seal in.
It suits nights rather than under makeup, and oilier or acne-prone skin may prefer to skip heavy occlusives on the face.

Slugging does not add moisture on its own, it seals in what is already there, so pair it with a hydrating step.

At Verdo we stock the Medik8 Advanced Night Restore and the Medik8 Total Moisture to support an overnight routine.

Disclaimer: This article is for general information only and is not medical advice. The studies cited are from peer-reviewed journals and are provided for educational context. Individual results vary. Speak with a qualified healthcare professional or dermatologist before changing your routine. Verdo Cosmetics makes no therapeutic claims about the products or services mentioned.

Frequently asked questions

What is slugging?

Slugging is sealing your skin with an occlusive layer, usually overnight, to slow water loss. The idea rests on well-established research showing occlusives like petrolatum reduce water loss and support barrier recovery (Ghadially et al., 1992).

Does slugging actually work?

Occlusives genuinely reduce water loss from the skin, which helps dry, dehydrated skin hold moisture and gives the barrier a better environment to repair. It seals in hydration rather than adding it.

Who should not slug?

Oilier and acne-prone skin may prefer to skip heavy occlusives on the face, since they can feel heavy. Slugging suits dry, dehydrated or chapped skin best.

Do I apply slugging over dry skin?

No. Apply an occlusive over a hydrating serum or moisturiser, so there is water to seal in. On its own it does not add moisture.

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