A lotion is a low-viscosity topical preparation intended for application to the skin. By contrast, creams and gels have higher viscosity, typically due to lower water content.[ Lotions are applied to external skin with bare hands, a brush, a clean cloth, or cotton wool.While a lotion may be used as a medicine delivery system, many lotions, especially hand lotions and body lotions are meant instead to simply smooth, moisturize, soften and perhaps perfume the skin.Some skincare products, such as sunscreen and moisturizer, may be available in multiple formats, such as lotions, gels, creams, or sprays.
Dermatologists can prescribe lotions to treat or prevent skin diseases. It is not unusual for the same drug ingredient to be formulated into a lotion, cream and ointment. Creams are the most convenient of the three but are inappropriate for application to regions of hairy skin such as the scalp, while a lotion is less viscous and may be readily applied to these areas (many medicated shampoos are in fact lotions). Historically, lotions also had an advantage in that they may be spread thinly compared to a cream or ointment and may economically cover a large area of skin, but product research has steadily eroded this distinction.
Since health care workers must wash their hands frequently to prevent disease transmission, hospital-grade lotion is recommended to prevent skin dermatitis caused by frequent exposure to cleaning agents in the soap. A 2006 study found that application of hospital-grade lotion after hand washing significantly reduced skin roughness and dryness.Care must be taken not to use consumer lotions in a hospital environment, as the perfumes and allergens may be a danger to those who are immunodeficient.
Most lotions are oil-in-water emulsions using a substance such as cetearyl alcohol to keep the emulsion together, but water-in-oil lotions are also formulated. The key components of a skin care lotion, cream or gel emulsion (that is mixtures of oil and water) are the aqueous and oily phases, an emulgent to prevent separation of these two phases, and, if used, the drug substance or substances. A wide variety of other ingredients such as fragrances, glycerol, petroleum jelly, dyes, preservatives, proteins and stabilizing agents are commonly added to lotions.