ATC Group: S02A Antiinfectives

Acetic acid is indicated for the treatment of superficial infections of the external auditory canal.

Boric Acid is a weakly acidic hydrate of boric oxide with mild antiseptic, antifungal, and antiviral properties. The exact mechanism of action of boric acid is unknown; generally cytotoxic to all cells. It is used in the treatment of yeast infections and cold sores.

Chloramphenicol is a broad spectrum antibiotic which has activity against many types of Gram-positive and Gram-negative bacteria. It acts by interfering with bacterial protein synthesis. Chloramphenicol is widely distributed in body tissues and fluids and enters the cerebrospinal fluid.

Chlorhexidine is an antimicrobial agent, active against a broad spectrum of Gram-positive and Gram-negative organisms, yeasts, fungi, opportunistic anaerobes and aerobes. Chlorhexidine is mainly a “membrane-acting” agent that destroys the outer membrane of the bacteria. It is inactive on bacterial spores unless the temperatures are high.

Ciprofloxacin is a fluoroquinolone antibacterial agent. The bactericidal action of ciprofloxacin results from the inhibition of both type II topoisomerase (DNA-gyrase) and topoisomerase IV, required for bacterial DNA replication, transcription, repair and recombination.

Fosfomycin exerts a bactericidal effect on proliferating pathogens by preventing the enzymatic synthesis of the bacterial cell wall. Fosfomycin inhibits the first stage of intracellular bacterial cell wall synthesis by blocking peptidoglycan synthesis.

Gentamicin is usually bactericidal in action. Although the exact mechanism of action has not been fully elucidated, the drug appears to inhibit protein synthesis in susceptible bacteria by irreversibly binding to 30S ribosomal subunits.

Hydrogen peroxide is used as a disinfectant and deodorant. It releases oxygen when applied to tissues, the effect lasts only as long as the oxygen is being released and is of short duration. The antimicrobial effect of the liberated oxygen is reduced in the presence of organic matter.

Miconazole possesses an antifungal activity against the common dermatophytes and yeasts as well as an antibacterial activity against certain gram-positive bacilli and cocci. Its activity is based on the inhibition of the ergosterol biosynthesis in fungi and the change in the composition of the lipid components in the membrane, resulting in fungal cell necrosis.

Neomycin is an aminoglycoside antibiotic and acts by binding to polysomes, inhibiting protein synthesis and generating errors in the transcription of the genetic code.

Ofloxacin is a quinolone-carboxylic acid derivative with a wide range of antibacterial activity against both Gram-negative and Gram-positive organisms. The primary mode of action of the quinolones is the specific inhibition of bacterial DNA gyrase. This enzyme is required for DNA replication, transcription, repair and recombination.

Polymixin B is bactericidal against a wide range of gram negative bacilli. It exerts a bactericidal effect by binding to acid phospholipids in the cell wall and membranes of the bacterium, thereby rendering ineffective the osmotic barrier normally provided by the cell membrane.

Tetracyclines are taken up into sensitive bacterial cells by an active transport process. Once within the cell they bind reversibly to the 30S subunit of the ribosome, preventing the binding of aminoacyl transfer RNA and inhibiting protein synthesis and hence cell growth.