Free guide · no signup
Slugging: what it is, and who should avoid it
Slugging is a thin layer of petrolatum over your night routine to slow water loss, and it works for dry or irritated skin at two or three nights a week. It is a poor bet if you are acne-prone, because it seals sebum and residue against the follicle all night. If new congestion appears within a week or two, stop; that is not a purge.
CostFree
Read3 min
SignupNone
VerdictNot for acne-prone
Verdict
Not for acne-proneGood for dry skin, risky if you are acne-prone
Build your routine: Should you slug? →What slugging does
An occlusive is a water-resistant film that sits on the surface and slows transepidermal water loss. Petrolatum is the most effective widely available one, which is why it is the default choice. Applied over your usual moisturizer at night, it holds water in the upper layers while you sleep. The film itself is inert, which is part of why petrolatum is so well tolerated by irritated skin.
It does not hydrate on its own. There is nothing moisturizing about a barrier film; it only keeps in what is already there. That is why it goes last, over a hydrating layer, and why applying it to dry, unmoisturized skin gives a far smaller benefit than people expect. Pair it with a humectant or a ceramide moisturizer underneath and the combination does considerably more than either alone.
Who it helps
It helps genuinely dry skin, skin in cold or low-humidity conditions, and barriers that have been irritated by over-exfoliation or a retinoid ramped up too fast. In those situations it is a cheap and reliable way to reduce discomfort and flaking while the barrier recovers over a week or two.
It is also useful in patches rather than all over: dry cheeks, flaking around the nose, chapped areas at the edges of the mouth. Targeted use avoids most of the downsides, and there is no requirement to coat the whole face to get the benefit where you need it. Spot use is also the sensible way to test whether it suits you at all before committing to the whole face.
Who should avoid it
If you are acne-prone, slugging is a poor bet. Petrolatum itself is not strongly comedogenic, but sealing sebum, sweat, and residue under a film all night is a reasonable way to provoke congestion and breakouts on skin already inclined toward them. Plenty of people report exactly that outcome. If you already break out along the jaw or forehead, those are the areas to leave uncovered.
Oily skin generally has no use for it either, since water loss is not the problem being solved. If you want to try it despite being acne-prone, restrict it to dry patches, avoid the areas where you break out, and stop if congestion appears rather than waiting it out. Treat any new congestion as a signal to stop rather than as a purge that will clear on its own.
Doing it sensibly
Apply your usual night routine, wait for it to absorb, then add a thin layer of occlusive as the final step. A thin layer is enough; more does not seal better and only makes a mess of your pillowcase. Two or three nights a week is plenty for most people who benefit.
Tonight, if your skin is dry or flaking, apply your moisturizer, wait for it to absorb, then a thin layer of petrolatum on the dry patches only, and never on a retinoid or acid night. If you break out along the jaw or forehead, leave those areas bare. The slugging quiz weighs your skin type, acne history, and climate and says whether to do it at all. The SkinPal app tracks hydration and breakouts over the following weeks so you can see which way it went.
FAQ
Common questions
What is slugging in skincare?+
Applying a thin layer of an occlusive such as petrolatum over your night routine to slow overnight water loss. It seals in what is underneath rather than adding hydration itself.
Does slugging cause acne?+
It can contribute to congestion on acne-prone skin by sealing sebum and residue under a film overnight. If you break out easily, limit it to dry patches or skip it entirely, and stop if new congestion appears within a week or two.
Can I slug over retinol?+
Not advisable. The occlusive layer increases contact and penetration, which raises the chance of irritation. Use the retinoid on its own nights and slug on recovery nights instead.
How often should I slug?+
Two or three nights a week is enough for most people who benefit, and even less if your skin is only occasionally dry. Nightly use is rarely necessary outside of very dry conditions.