Effect of nystatin and chlorhexidine digluconate on Candida albicans.

Polyene antibiotics such as nystatin and amphotericin B are among the most widely recommended drugs for use against oral candidiasis. It is also generally accepted that chlorhexidine gluconate is an appropriate adjunct or an alternative to specific antimycotic drugs. The aim of the present study was to examine the effect of the combination of nystatin and chlorhexidine digluconate on Candida albicans in vitro. The minimum inhibitory concentration (MIC) value for the combination of the two drugs was found to be significantly higher than the values for each of the drugs alone, approximately 33 times the MIC value for the nystatin solution and 4 times the value for chlorhexidine digluconate. The results of the MIC study and the presence of a precipitate in all combinations of nystatin and chlorhexidine digluconate showed that the combination of the drugs is not effective in vitro against Candida albicans. The most likely reason is that a low solubility chlorhexidine-nystatin salt is formed, thus rendering the combined drug complex ineffective as an antibiotic agent.