1.1. INTRODUCTION

 An antiseptic is a substance that inhibits the growth and development of microorganisms and does not necessarily have to be destructive to the microorganisms. They are routinely used as topical agents, for application on the skin, mucous membranes, and inanimate objects to inhibit the activities of microorganisms on these surfaces, and are mainly used as wash solutions.

Antiseptics are a diverse class of organic and inorganic substances which are applied to skin surfaces or mucous membranes for their anti-infective effects. Their uses include cleansing of skin and wound surfaces after injury, preparation of skin surfaces prior to injections or surgical procedures, and routine disinfection of the oral cavity as part of a program of oral-hygiene. Disinfectants are related family of antimicrobial agents that are used for disinfection of inanimate objects, including instruments and furniture surfaces. Some substances could qualify to be an antiseptic and also an antiseptic.

Commonly used antiseptics for skin cleaning include benzalkonium chloride, chlorhexidine, hexachlorophine, iodine compounds, mercury compounds, alcohol and hydrogen peroxide. Other agents which have been used for this purpose, but have largely been supplanted by more effective or safer agents, include boric acid and volatile oils such as methyl salicylate (oil of wintergreen).

Chlorhexidine is applied on the mucous membranes, and has been used in oral rinses and preoperative total body washes with long term record of safety (Micromedex Consumer Medication Information, 2017). Benzalkonium chloride and hexachlorophine are used primarily as hand scrubs or face washes. Benzalkonium may also find application as a disinfecting agent for instruments, and in low concentration as a preservative for drugs including ophthalmic solutions. Benzalkonium chloride is inactivated by organic compounds, including soap, and must not be applied to areas which have not been fully rinsed.

Iodine compounds include tincture of iodine and povidone iodine compounds. Iodine compounds have the broadest spectrum of all topical antimicrobial agents, with action against bacteria, fungi, viruses, spores, protozoa, and yeasts. Iodine tincture is highly effective, but its alcoholic component is drying and extremely irritating when applied to abraided skin. Povidone iodine, an organic compound, is less irritating and less toxic, but not as effective. Povidone iodine has been used for hand scrubs and disinfection of surgical sites. Aqueous solutions of iodine have also been used as antiseptic agents, but are less effective than alcoholic solutions and less convenient to use than the povidone iodine compounds.