Final answer:
Chlorhexidine is a broad-spectrum bisbiguanide antiseptic that is bacteriostatic at low concentrations and bactericidal at high concentrations. It is used for infection control in various clinical settings, most notably as a surgical scrub and for oral hygiene. However, it is not effective against all pathogens and can cause tooth discoloration.
Step-by-step explanation:
Chlorhexidine is a cationic antiseptic compound that is part of the bisbiguanides family. This antiseptic has a broad-spectrum activity against various microorganisms, including yeasts, gram-positive bacteria, and some gram-negative bacteria, making it widely used for infection control in various settings.
There are two main effects of chlorhexidine on bacterial cells. At lower concentrations, chlorhexidine is bacteriostatic, where it inhibits the growth and multiplication of bacteria by disrupting their cell membranes. At higher concentrations, it is bactericidal and leads to the congealing of cytoplasmic contents of bacterial cells, effectively killing them. Chlorhexidine's cell membrane disruption mechanism provides long-lasting antimicrobial activity, which is more persistent than that of iodophors.
In clinical settings, chlorhexidine is employed as a surgical scrub, for handwashing by medical personnel, and for topical antisepsis for patients before surgery or needle injection. This compound is also used in the form of solutions for oral rinses after dental procedures or to treat gingivitis. Its use is essential in the decolonization process in protocols designed to control the spread of MRSA (Methicillin-resistant Staphylococcus aureus).
Despite its effectiveness, chlorhexidine is not effective against all microorganisms, such as Pseudomonas aeruginosa—which can develop resistance, Mycobacterium tuberculosis, and nonenveloped viruses. It is also not sporicidal. Furthermore, chlorhexidine mouthwash can cause tooth surface discoloration, which may affect patient compliance.