Lidocaine + Chlorhexidine Gluconate + Metronidazole is a combination of three medicines: Lidocaine , Chlorhexidine Gluconate and Metronidazole, which treats mouth sores. Lidocaine is a local anesthetic which forms a protective coating over the mouth sores and blocks pain signals to further relieve pain. Chlorhexidine Gluconate is an antiseptic and disinfectant which effectively cleans out the ulcer surface to prevent infection. Metronidazole is an antibiotic which kills the bacteria and other microorganisms by damaging their DNA. Chlorhexidine Gluconate+Metronidazole prevents the growth of bacteria and helps in the healing of ulcers. It has antimicrobial action on the microorganisms causing infection. Due to this gum swelling is treated.