Safety of Hibitane. II. Human experience

Chlorhexidine has been widely used in medical practice since its introduction on to the marked in the early 1950s. Primarily it has been used for topical antisepsis, e.g. pre-surgery skin preparation, burns prophylaxis, and prior to obstetrical/gynaecological procedures. This extensive experience has demonstrated the virtual absence of sensitization and a low irritancy potential for the compound. Only one significant adverse effect has been identified during medical use, namely, the production of sensorineural deafness after direct instillation into the middle ear, a property shared by several commonly used antiseptics. The encouraging reports of the use of chlorhexidine for plaque control prompted further safety investigations. It has been shown that absorption after oral ingestion is very low, and long-term oral use has not produced changes in haematological and biochemical parameters. Occasional oral intolerance of mouthrinse formulations has been reported, although no histological abnormalities were present in gingival biopsies taken after 18 months' daily use. Very occasionally, a reversible swelling of the parotid glands has been reported after use of chlorhexidine in mouthrinse formulations, but not after other methods of administration. Tooth discoloration, which shows wide inter-individual variation is seen after all dental formulations. This undesirable cosmetic effect would appear to represent the only significant argument against everyday prophylactic oral use of chlorhexidine.