Emollient is a term given to moisturizers used to treat dry, damaged or scaling skin. Any number of factors can result in dry skin, including diuretic medications; underactive thyroid gland; inherited factors; a skin condition such as atopic dermatitis (eczema), psoriasis or ichthyosis; dry air e.g., low winter humidity; exposure to the wind, over-washing; reduction in production of natural moisturizers (sebum) in old age; or any combination of these. Emollients are available as over-over-the-counter skin care products, as well as by prescription. They have two actions: one in which they provide a layer of oil on the surface of the skin to slow the loss of water through the skin and increase the natural moisture content. These are called Occlusives. The second type of emollient consists of substances that penetrate the skin to increase the skin’s own ability to retain water. These are called Humectants. Products that contain occlusive emollients include bath oils, lotions, creams and ointments. Products that are or contain Humectants include glycerin, urea and alpha hydroxyl acids. Some moisturizers contain both occlusives and humectants. Adverse reactions to emollients are rare, but some people experience an initial heat reaction or stinging when the emollient is applied. This is usually temporary. If you experience a burning or tingling sensation when you apply an emollient and it persists, you may need to try another brand until you find one that doesn’t cause a reaction.