Answer
Chlorhexidine can temporarily stain the teeth or tongue. Discolouration usually clears after treatment stops, although professional cleaning is occasionally required.
Sources for this answer
- Covonia Sore Throat 0.2/0.05%w/v Oromucosal Spray Lemon Flavour — Current selected SmPCemc · Summary of Product Characteristics
- NHSNHS · NHS medicine guidance
General medicine information. Follow the instructions for your own medicine and speak to a pharmacist or clinician about your individual circumstances.