Lotion

A lotion is a low- to medium-viscosity, topical preparation intended for application to unbroken skin. Most lotions are oil-in-water emulsions, but water-in-oil lotions are also formulated. Lotions are usually applied to external skin with bare hands, a clean cloth, cotton wool or gauze.

The key components of a lotion emulsion 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.

Lotions can be used for the delivery to the skin of medications such as:
 * Antibiotics
 * Antiseptics
 * Antifungals
 * Corticosteroids
 * Anti-acne agents
 * Soothing or protective agents (such as calamine)

Aside from medical use and usage in skin care, lotions are often used as accessories to aid massage, sex, or male masturbation.

It is not uncommon 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). Lotions also have an advantage in that they may be spread thinly compared to a cream or ointment and may economically cover a large area of skin. Non-comedogenic lotions are recommended for use on acne prone skin.