Iodine tincture, antiseptic/disinfectant

Of the four halogens, iodine is the weakest oxidizing agent. Tincture of iodine, a 10% solution of I2 in alcohol, is sometimes used as an antiseptic. Hospitals most often use a product called povidone-iodine, a quite powerful iodine-containing antiseptic and disinfectant, which can be diluted with water to the desired strength. These applications of molecular iodine should not delude you into thinking that the solid is harmless. On the contrary, if I2(s) is allowed to remain in contact with your skin, it can cause painful bums that are slow to heal. 

In 1881, Bernard Courtois (1777-1838) introduced another halogen, iodine, extracting the element from wracks at the seashore. William Wallace proposed iodine tincture in 1835 to disinfect wounds. It was superseded by iodoform, which was less of an irritant, invented by Georges Simon Serullas (1774-1832). Structurally, it was very comparable to chloroform, the chlorine atom being substituted by an iodine one. Aqueous iodine solutions were proposed by Casimir Davaine (Lugol s solution) as antiseptics. 

Medical Usage. Isopropyl alcohol is also used as an antiseptic and disinfectant for home, hospital, and industry (see Disinfectants and antiseptics). It is about twice as effective as ethyl alcohol in these appHcations (153,154). Rubbing alcohol, a popular 70 vol % isopropyl alcohol-in-water mixture, exemplifies the medicinal use of isopropyl alcohol. Other examples include 30 vol % isopropyl alcohol solutions for medicinal liniments, tinctures of green soap, scalp tonics, and tincture of mercurophen. It is contained in pharmaceuticals, eg, local anesthetics, tincture of iodine, and bathing solutions for surgical sutures and dressings. Over 200 uses of isopropyl alcohol have been tabulated (2). 

Disinfection destroys pathogenic organisms. This procedure can render an object safe for use. Disinfectants include solutions of hypochlorites, tinctures of iodine or iodophores, phenoHc derivatives, quaternary ammonium salts, ethyl alcohol, formaldehyde, glutaraldehyde, and hydrogen peroxide (see Disinfectants AND antiseptics). Effective use of disinfected materials must be judged by properly trained personnel. 

However, the efficacy of their disinfection programmes encouraged other hospitals to adopt the practices. Other antiseptic preparations rose in popularity towards the end of the 19th century, most notably, various chloramines like chloramine T and halazone (which slowly release hypochlorous acid), tincture of iodine and iodoform but it was the intro-... 

Iodine has different medical uses. The antiseptic tincture of iodine (3% iodine and 2.5% potassium iodide in alcohol) has been known since 1828. PVPI is a modern disinfectant with 1-3% iodine, bound in a complex way to polyvinylpyrroHdone. It is ap-pHed to the skin before surgical operations. Iodine is used as an alternative to chlorine for disinfection of drinking water. Even in such small concentrations as 1 ppm, iodine has a positive effect and is without the negative secondary effects characteristic of chlorine. 

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