ICD-10 Specific code H62.1: Otitis externa in viral diseases classified elsewhere

Acyclovir is an antiviral agent with activity against herpes simplex virus and varicella-zoster virus. Acyclovir inhibits the DNA polymerase of the virus, preventing further proliferation.

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.

Clobetasone is a topical corticosteroids. Clobetasone has little effect on hypothalamo-pituitary-adrenal function. Clobetasone is less potent than other available corticosteroid preparations and has been shown not to suppress the hypothalamo-pituitary-adrenal axis in patients treated for psoriasis or eczema.

Erythromycin exerts its antimicrobial action by binding to the 50S ribosomal sub-unit of susceptible microorganisms and suppresses protein synthesis. Erythromycin is bacteriostatic and bactericidal depending on its concentration and the type of organism.

Hydrocortisone is the main glucocorticoid secreted by the adrenal cortex. Hydrocortisone is an anti-inflammatory steroid. Its anti-inflammatory action is due to reduction in the vascular component of the inflammatory response and reduction in the formation of inflammatory fluid and cellular exudates.

Minocycline is a semi-synthetic derivative of tetracycline. Minocycline inhibits protein synthesis in susceptible bacteria. In common with other tetracyclines it is primarily bacteriostatic and has a similar spectrum of activity to other tetracyclines.

Piperacillin is a broad-spectrum, semisynthetic penicillin. Piperacillin exerts bactericidal activity by inhibition of both septum and cell-wall synthesis.

Sultamicillin is the tosylate salt of the double ester of sulbactam plus ampicillin. Sulbactam is a semisynthetic beta-lactamase inhibitor which, in combination with ampicillin, extends the antibacterial activity of the latter to include some beta-lactamase-producing strains of bacteria that would otherwise be resistant.

Ticarcillin disrupts bacterial cell wall development by inhibiting peptidoglycan synthesis and/or by interacting with penicillin-binding proteins.

Valaciclovir, an antiviral, is the L-valine ester of aciclovir. Valaciclovir is rapidly and almost completely converted in man to aciclovir and valine. Aciclovir is a specific inhibitor of the herpes viruses with in vitro activity against herpes simplex viruses (HSV) type 1 and type 2, varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr Virus (EBV), and human herpes virus 6 (HHV-6).