ChEBI: A bisbiguanide compound with a structure consisting of two (p-chlorophenyl)guanide units linked by a hexamethylene bridge.
Chlorhexidine is an antibacterial used for numerous applications. It is a cationic polybiguanide (bisbiguanide) used primarily as its salts, dihydrochloride, diacetate, and digluconate. Chlorhexidine is one of those drugs which are enlisted/included in the World Health Organization's List of Essential Medicines, a list of the most important drugs needed in a basic health system.
- Chlorhexidine is used as a germicidal compound in teat dips. Also used as navel treatment, udder and eye wash, surgical scrub and sterilization material.
- Chlorhexidine is used primarily as a topical antiseptic/disinfectant in wound healing, at catheterization sites, in various dental applications and in surgical scrubs. it is used as an antibacterial agent in humans to control gingivitis and over all plaque control in preventative dentistry.
- Hydrogenolysis of benzyl-nitrogen bonds.
Chlorhexidine is a cationic broad-spectrum antimicrobial agent belonging to the bis(biguanide) family. Its mechanism of action involves destabilization of the outer bacterial membrane. It is effective on both Gram-positive and Gram-negative bacteria, although it is less effective with some Gram-negative bacteria. It has both bactericidal and bacteriostatic mechanisms of action.
Chlorhexidine's antimicrobial effects are associated with the attractions between chlorhexidine (cation) and negatively charged bacterial cells. After chlorhexidine is absorpted onto the organism's cell wall, it disrupts the integrity of the cell membrane and causes the leakage of intracellular components of the organisms.
Aqueous solutions of chlorhexidine are most stable within the pH range of 5-8. Above pH 8.0 chlorhexidine base is precipitated and in more acid conditions there is gradual deterioration of activity because the compound is less stable. Chlorhexidine is used primarily as a topical antiseptic/disinfectant in wound healing, at catheterization sites, in various dental applications and in surgical scrubs. It has a LD-50 orally in mice as a diacetate at 2gm./kg. In digluconate form the LD-50 is 1800 gm./kg.
Chlorhexidine (CHX) was the first antimicrobial agent shown to inhibit dental plaque formation and the development of chronic gingivitis (Loe and Schiott 1970).
Chlorhexidine is a cationic chlorophenyl bisbiguanide antiseptic.
Bisbiguanides are the primary second generation antiplaque agents exhibiting considerable substantivity and broad spectrum antibacterial properties.
In dental medicine, CHX was initially used for disinfection of the oral cavity prior to oral surgical procedures and in endodontics. Plaque inhibition by CHX was first investigated in 1969 (Schroeder) but the first controlled clinical study was performed by Loe and Schiott (1970).  This study showed that rinsing for 60 sec, twice a day with 10 ml of a 0.2% (20 mg dose) CHX gluconate solution, in the absence of normal tooth cleaning, inhibited plaque regrowth and the development of gingivitis.
CHX is one of the most widely investigated and used antiplaque agents.The advantage of CHX over other cationic agents is that it can bind strongly to many sites in the oral cavity and is released slowly over 7 to 12 hours after rinsing, thus providing considerable substantivity and a sustained antimicrobial effect restricting bacterial proliferation. CHX binds strongly with anionic glycoproteins and phosphoproteins on the oral mucosa and tooth pellicle in addition to its property of binding to the surfaces of bacterial cell membranes affecting the cells ability to adhere. CHX is considered the most potent chemotherapeutic agent currently available.