Antimicrobials: Dr MY Ansari Antimicrobial agents are the chemicals and their preparation in reducing or preventing infection due to microorganisms Antiseptic Disinfectants Germicides Bacteriostatic Living nonliving Kill No growth

Definition Antiseptic: Any agent which kills or inhibits the growth of microorganisms found in living tissue. Disinfectant: Any agent which kills or inhibits the growth of microorganisms found in inanimate objects. Germicide: General term for fungicide, bactericide, amoebicide

Classification of Antiseptics and Disinfectants (according chemical structure) Inorganic substances 1. Halogens: Iodine (2%, 3%, 5% alcochol solution) Iodinolum Povidon-Iod (Betadinum) Iodophorm Lugol’s solution Chloramine B Chlorhexidine bigluconate Pantocidum (Halazone)

Continue… 2. Oxidizing agents: Hydrogen peroxide Potassium permanganate 3. Acids and alkalis: Boric acid Salicylic acid Solution of ammonia 4. Metallic salts: Silver nitrate Copper sulfate Zinc sulfate Zinc oxide

Potassium permanganate Potassium permanganate as a medication, it is used for a number of skin conditions. This includes fungal infections of the foot, superficial wounds, dermatitis, and tropical ulcers.

Potassium permanganate 2KMnO4 + H2O = 2KOH + 2MnO2 + 3O2 It liberates oxygen in atomic form. Highly water soluble, used in 1:4,000-1:10,000 solution. Higher concentrations cause burns. Clinical uses: Gargling, irrigating cavities, urethra and wounds. Stomach wash in alkaloid poisoning. In a 2-5% solution is used for burns, bites of mosquitoes and snakes, for quick healing of wounds. Disinfection of water.

Halogens Chlorine Discovered in 1774 by a Swede and Scheele It is a pale green, toxic, reactive gas It is a powerful irritant and toxin Used as a gas warfare agent in WWI very horrible, lifelong damage on those who survived The damaged lungs were possibly a factor in the 1918 flu pandemic Solution of chlorine in water is both a powerful bleach and disinfectant

The mechanism of antimicrobial action Halogens The mechanism of antimicrobial action Denaturation of proteins of the protoplasm of microbial cells by reacting with the amino group of the proteins, displacing hydrogen. Denatured protein loses its activity. In the presence of organic substances halogen’s antimicrobial effect decreases.

Halogens Chloramine is used in drinking water treatment instead of chlorine because it produces less disinfection by products. Chlorine is used to disinfect swimming pools, and is added in small quantities to drinking water to reduce waterborne diseases. Hypochlorites (Sodium hypochlorite), often in the form of common household bleach, are used in the home to disinfect drains, and toilets. Other hypochlorites such as calcium hypochlorite are also used, especially as a swimming pool additive. Hypochlorites yield an aqueous solution of hypochlorous acid that is the true disinfectant. Hypobromite solutions are also sometimes used. Iodine is usually dissolved in an organic solvent or as Lugol's iodine solution. It is used in the poultry industry. It is added to the birds' drinking water. Although no longer recommended because it increases scar tissue formation and increases healing time, tincture of iodine has also been used as an antiseptic for skin cuts and scrapes.

Iodines Iodine - active bactericidal element. At a dilution of 1: 20 000 - kill forms of bacteria for 1 min. Preapration of Alcoholic solution of Iodine 5% (5 g of Iodine, KI -2g, ethyl alcohol 95% 100ml) An irritant and a distraction action INDICATIONS: Disinfection of the surgical field, disinfection of wounds, the surgeon's hands.