- Occlusive is a term primarily used in dermatology and skincare to describe substances or agents that form a physical barrier on the surface of the skin to prevent transepidermal water loss (TEWL). These substances work by creating a protective film that traps moisture in the skin, thereby maintaining hydration and improving the skin’s barrier function.
- Occlusives are particularly beneficial for individuals with dry, dehydrated, or compromised skin, as they help restore suppleness and prevent further moisture loss caused by environmental factors such as wind, cold, or low humidity.
- Common occlusive ingredients include petrolatum (petroleum jelly), lanolin, mineral oil, beeswax, dimethicone (a type of silicone), and certain plant-based oils and butters like shea butter and cocoa butter. Among these, petrolatum is considered one of the most effective occlusives, capable of reducing water loss from the skin by up to 99%. These ingredients are often used in creams, ointments, balms, and lotions designed to treat very dry or irritated skin conditions, such as eczema, psoriasis, and dermatitis.
- Occlusives differ from other moisturizing agents like humectants and emollients. While humectants (e.g., glycerin, hyaluronic acid) attract water to the skin, and emollients (e.g., squalane, fatty acids) smooth and soften the skin surface, occlusives primarily act as a sealant to lock in the moisture provided by these other ingredients. This is why skincare formulations often combine all three types of moisturizers to create comprehensive hydration and barrier repair.
- While highly effective, occlusives can have some drawbacks, particularly for those with oily or acne-prone skin. The barrier they form can sometimes feel heavy or greasy, and in certain individuals, they may exacerbate breakouts by trapping sebum and bacteria. Therefore, selecting the appropriate type and concentration of occlusive ingredient is important based on skin type and specific needs. Non-comedogenic occlusives like dimethicone are often preferred in formulations for acne-prone or sensitive skin.
- In medical and therapeutic contexts, occlusive dressings are used to promote wound healing. These dressings cover the wound completely, protecting it from infection and mechanical injury while maintaining a moist environment that facilitates faster tissue regeneration. Occlusive therapy is also employed in dermatology to enhance the absorption of topical medications, such as corticosteroids, by trapping them against the skin under a sealed dressing or wrap.
