A hand sanitizer or hand antiseptic is a supplement or alternative to hand washing with soap and water. Various preparations are available, including gel, foam, and liquid solutions. The active ingredient in hand sanitizers may be isopropanol, ethanol, n-propanol, or povidone-iodine. Inactive ingredients in alcohol rubs typically include a thickening agent such as polyacrylic acid for alcohol gels, humectants such as glycerin for liquid rubs, propylene glycol, and essential oils of plants. Alcohol based hand sanitizers are more effective at killing microorganisms than soaps and do not dry out hands as much.
Common non-alcohol, rinse-free hand sanitizers use either small concentrations of the nitrogenous cationic surface-acting agent benzalkonium chloride, the chlorinated aromatic compound triclosan, or povidone-iodine. Some products claim to kill microorganisms naturally, although these claims are not substantiated in any FDA monograph. All hand sanitizer products require National Drug Code designation in United States and natural product number designation in Canada.