Rivacol Chlorhexidine Mouthwash, in a mint flavoured aqueous base, is a disinfectant and antiseptic mouthwash effective against a wide range of vegetative Gram-positive and Gram-negative organisms, some viruses and some fungi.It is ineffective against bacterial spores at room temperature, and acid-fast bacteria are inhibited but not killed. It is more active against Gram-positive than Gram-negative bacteria, and some species of Pseudomonads and Proteus are relatively less susceptible. Chlorhexidine activity may be reduced by blood and other organic matter.