---
title: "Occlusives — Glossary | School of Dermatology"
description: "Understand occlusive moisturizing ingredients, how they seal in hydration, and why petrolatum, dimethicone, and other occlusives are essential for dry skin."
lang: en
json-ld: |
  [
    {
      "@context": "https://schema.org",
      "@type": "DefinedTerm",
      "name": "Occlusives",
      "description": "Occlusives are a category of moisturizing ingredients that work by forming a physical barrier on the skin's surface to prevent transepidermal water loss (TEWL). They essentially seal moisture in by creating a protective film that slows evaporation. Common occlusive ingredients include petrolatum (petroleum jelly, the most effective occlusive), dimethicone (a silicone), beeswax, squalane, mineral oil, lanolin, and shea butter. Occlusives are particularly beneficial for very dry or compromised skin, eczema, and in cold or dry climates where TEWL is accelerated. They are typically applied as the last step in a skincare routine, on top of humectants and emollients, to lock in all the hydration beneath. While some people worry that occlusives clog pores, most (especially petrolatum and dimethicone) are actually non-comedogenic. The concept of 'slugging' — applying a layer of petrolatum as the final step — has gained popularity for intense overnight barrier repair.",
      "url": "https://schoolofdermatology.com/glossary/occlusives",
      "inDefinedTermSet": {
        "@type": "DefinedTermSet",
        "name": "School of Dermatology Skincare Glossary",
        "url": "https://schoolofdermatology.com/glossary"
      }
    },
    {
      "@context": "https://schema.org",
      "@type": "BreadcrumbList",
      "itemListElement": [
        {
          "@type": "ListItem",
          "position": 1,
          "name": "Home",
          "item": "https://schoolofdermatology.com"
        },
        {
          "@type": "ListItem",
          "position": 2,
          "name": "Glossary",
          "item": "https://schoolofdermatology.com/glossary"
        },
        {
          "@type": "ListItem",
          "position": 3,
          "name": "Occlusives",
          "item": "https://schoolofdermatology.com/glossary/occlusives"
        }
      ]
    }
  ]
---

[![School of Dermatology](/assets/logo-AGZDufdq.svg)](/)

Articles

[Skin Types](/skin-types)

Tools

[Glossary](/glossary)

[Home](/)/ [Glossary](/glossary)/ Occlusives 

Glossary 

# Occlusives

uh-KLOO-sivz 

## Definition

Occlusives are a category of moisturizing ingredients that work by forming a physical barrier on the skin's surface to prevent transepidermal water loss (TEWL). They essentially seal moisture in by creating a protective film that slows evaporation. Common occlusive ingredients include petrolatum (petroleum jelly, the most effective occlusive), dimethicone (a silicone), beeswax, squalane, mineral oil, lanolin, and shea butter. Occlusives are particularly beneficial for very dry or compromised skin, eczema, and in cold or dry climates where TEWL is accelerated. They are typically applied as the last step in a skincare routine, on top of humectants and emollients, to lock in all the hydration beneath. While some people worry that occlusives clog pores, most (especially petrolatum and dimethicone) are actually non-comedogenic. The concept of 'slugging' — applying a layer of petrolatum as the final step — has gained popularity for intense overnight barrier repair.

## Related Terms

[Humectant](/glossary/humectant)[Emollient](/glossary/emollient)[Transepidermal Water Loss (TEWL)](/glossary/transepidermal-water-loss-tewl)[Barrier Function](/glossary/barrier-function)

Was this definition helpful?

In This Entry

[Definition](#definition)[Related Terms](#related-terms)

More "O" Terms

[Oxidative Stress](/glossary/oxidative-stress)

#### Ingredients

-   [Browse All](/topics/ingredients)

#### Treatments

-   [Browse All](/topics/treatments)

#### Skin Concerns

-   [Browse All](/topics/skin-concerns)

#### Light Therapy

-   [Browse All](/topics/light-therapy)

#### Skin Care

-   [Browse All](/topics/skin-care)

#### Hair Care

-   [Browse All](/topics/hair-care)

#### Resources

-   [Skincare Glossary](/glossary)
-   [All Articles](/articles)
-   [Contact Us](/contact)

© 2026 School of Dermatology. All rights reserved. For educational purposes only.

[Privacy Policy](/privacy-policy)[Terms of Service](/terms-of-service)[Disclaimer](/disclaimer)

![](https://bat.bing.com/action/0?ti=343074860&Ver=2&mid=6ae8496e-3582-46e5-b115-7edb16f2f5bb&bo=1&sid=726fde30aafb11f184770f3ce691905e&vid=72700470aafb11f188c889c823811c01&vids=0&msclkid=N&pi=918639831&lg=en-US&sw=800&sh=600&sc=24&nwd=1&tl=Occlusives%20%E2%80%94%20Glossary%20%7C%20School%20of%20Dermatology&p=https%3A%2F%2Fderm-school-hub.lovable.app%2Fglossary%2Focclusives&r=&lt=1073&evt=pageLoad&sv=2&cdb=AQAQ&rn=403847)

![](https://bat.bing.com/action/0?ti=343220809&Ver=2&mid=fe9cdd22-03a2-4914-9a69-7de4815e54f8&bo=1&sid=726fde30aafb11f184770f3ce691905e&vid=72700470aafb11f188c889c823811c01&vids=1&msclkid=N&pi=918639831&lg=en-US&sw=800&sh=600&sc=24&nwd=1&tl=Occlusives%20%E2%80%94%20Glossary%20%7C%20School%20of%20Dermatology&p=https%3A%2F%2Fderm-school-hub.lovable.app%2Fglossary%2Focclusives&r=&lt=1073&evt=pageLoad&sv=2&cdb=AQAQ&rn=949001)